FREQUENTLY ASKED QUESTIONS

We are here to help you get answers to your questions about OneSimCard phones and services.

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31. OneSim VoIP
    • When making an outgoing call how do I select which way the call should go: through regular roaming or through OneSim VoIP?

      To make an outgoing call using OneSim VoIP, you need to be registered on a Wi-Fi network and have the OneSim VoIP app running on your phone. You should make the call using the OneSim VoIP app dial pad. To make a call the regular roaming way,you should make a call from your regular phone dial pad. 

      NOTE: Regular roaming calling is NOT available on DataMax or DataMax eSIM cards. To use voice you will need to use the OneSim VoIP app

32. OneSim VoIP
    • Does voicemail work with OneSim VoIP?

      Yes. If you are not available to answer the OneSim VoIP call or if the OneSim VoIP app is turned off, the call will be routed through our standard roaming network. If the call is not answered it will be sent to your OneSimCard voicemail box. 

      NOTE: Voicemail is not available for DataMax or DataMax eSIM cards with OneSim VoIP.

33. eSIM
    • How does eSIM works?

      eSIM is not a physical SIM. It is a piece of software downloaded to a compatible phone. So there is no shipping involved with delivering eSIM.


      eSIM makes your iPhone or Pixel phone to be a dual SIM phone. This means that you can use two sim cards on the phone at the same time. You can select which SIM card is used for calls and texts, and which one is used for data. You can select which sim card is to be the primary and which one not to be used. You can make these changes from the settings of your phone at any time. In short - eSIM offers greater flexibility to your eSIM compatible phone. It allows you to use the service provider of your choice - whether you are traveling or staying home.


      OneSimCard eSIM can be installed only on a single device. It can't be moved to another device, but it can be re-installed on the original device up to 10 times if required.
34. Troubleshooting Questions
    • I just activated my SIM card and can't make a successful test call. What's wrong?

      If you just activated your SIM card and can not make a test call by following the instructions in the user manual, you will likely just need to power off the phone and power it back on again. The phone should automatically re-register with one of our partner networks. Remember, if you answer the test call when it rings you will be charged for the call.
      We strongly recommend you to watch very short video tutorials that will help you to understand how to make calls, SMS and data on your OneSimCard Phone.

      These videos are available in the Help Menu of your OneSimCard Portal. You need to log in to your OneSimCard account first and then proceed to the Help Menu to be able to access these videos.

35. Troubleshooting Questions
    • When I dial following your instructions it does not work. What's wrong?

      This answer applies to SIM cards purchased before January 1, 2017.

      Some phones, such as Samsung, some Motorola, Android and Apple iPhones, require special dialing instructions or simple OneSimCard settings menu changes in order to make calls.

      It is possible to make almost any phone entirely compatible, so you can call directly without using the OneSimCard menu or *146* by following these simple programming instructions below.

      How to activate compatibility mode:

        1. Locate OneSimCard Menu.

       On iPhones it is called SIM Applications menu and is located under Settings- Phone menu

               On Androids it is called SIM Toolkit app or OneSimCard app and it looks like one of the apps.

         

      1. Open "OneSimCard" menu ( SIM Applications, SIM Toolkit, STK)
      2. Select "Settings
        Newer SIM Cards: Select Service Code option and follow instructions below:
        Older SIM Cards: After selecting Settings:
        1. Agree with message by pressing "Yes"
        2. Dial digits "1101" and select "OK" (Screen will show "CC OptionX: ON" message)

          Bear in mind that if you have powered your telephone down, and have removed and reinstalled the battery, you will need to follow the programming steps outlined above, again.

          If for any reason after entering compatibility code, you still do not get a ringback or you get the ringback the first time you make a call, but second time it would not work, please enter code 802 into the Service Code window instead of 1101 as provided above.

           

          iPhone users can download OneSimCard Assist App from iTunes that will takes care of the iphones compatibility issues, except for removing the ringback.


          For example, calling to USA: Dial *146*0016175551212# and press the TALK (or SEND) button

          * is a star character located on the keypad
          • To check your balance dial  *146*099# and press the TALK (or SEND) button
          • To add funds dial *146*098XXXX*ZZ# and press the TALK (or SEND) button,
            where XXXX - 4 last digit of your credit card on file, ZZ - Recharge amount
          • You need to press * on your phone in the above dialing sequences
          • Activation of voice mail *146*091# and press the TALK (or SEND) button
          • Deactivation of voice mail *146*090# and press the TALK (or SEND) button
          • Check number of messages in Voice Mail *146*094# and press the TALK (or SEND) button
          • To listen to voice mail *146*095# and press the TALK (or SEND) button

          The sequence *146* and # at the end can be used from any phone. However, most phones do not require it.

          We strongly recommend you to watch very short video tutorials that will help you to understand how to make calls, SMS and data on your OneSimCard Phone.


          These videos are available in the Help Menu of your OneSimCard Portal. You need to log in to your OneSimCard account first and then proceed to the Help Menu to be able to access these videos.
          Again, this troubleshooting advice might be needed only for older SIM cards.

           

           

      36. eSIM
        • Can I use Facetime, WhatsApp, Telegram, Discord, iMessage, and other messaging Apps with eSIM?

          Yes, you can use your messaging apps with eSIM World, which now offers a mobile number ID. 

          For DataMax eSIM, you can use these Apps as you already do. Please ensure your messaging account is already setup with your primary carrier’s phone number because you cannot sign up for these services with the DataMax eSIM number.

          Additionally, the eSIM data service can be used for the actual data part of your communications. So, when you are installing eSIM on phone, you can select the Primary service for Facetime and iMessage and then if your selected eSIM to be your primary data service, the communications will go over eSIM mobile data.

      37. Troubleshooting Questions
        • Does iPhone Hotspot work with OneSimCard?

          Yes. All unlocked iPhones' Hotspot feature works with OneSimCard SIM.

           
          There are a few settings to make sure for this to function properly on your iPhone:
          1. Settings - Cellular - Cellular Data - ON
          2. Settings - Cellular - Data Roaming - ON
          3. Settings - Cellular - Cellular Data Network - Cellular Data - APN = APN will be set automatically
          4. Settings - Wi-Fi - ON
          5. Settings - Personal Hotspot - ON. 
          After turning the Hotspot on, you should stay on the Personal Hotspot screen of your iPhone for SSID of your phone to show up on other Wi-Fi devices, so you can get connected. After you connected to the Hotspot, you can leave the screen. Alternatively, you can always use Bluetooth or USB connection to provide the internet access from your OneSimCard iPhone Hotspot to your other devices.
      38. How To Use Questions
        • How do I set up SMS text messaging on my phone?

          SMS messaging usually works without any additional setup of the phone.
          In rare cases when there are issues sending or receiving text messages, please look at the following:

          Problem with Sending SMS:

          • Incorrect SMSC number (SMS Service Center Address) in handset settings.

          SMSC number should be set as follows:

           

          1. For Standard  and Plus OneSimCard SIM: +3725099000 for all countries except:

          a. China:  +85290296747

           

          2. For the Expedition (former Data & Roam) SIM as well as for Europe & More SIM: +37256100041

           

          Special instructions for Apple Phones:

          With Apple iPhones to check SMSC:

          From the phone dialer Dial *#5005*7672# 

          You will see the SMSC set currently on the phone. 

          To change the SMSC on Iphone dial: 

          Plus and Standard SIMs: **5005*7672*+3725099000# for all countries except China and **5005*7672*+85290296747# if in China.

          Expedition (formerly Data & Roam) and Europe & More SIMs in any country: **5005*7672*+37256100041#

           

          If your phone requires the name of Message Center Name enter: SMSC
          SMS lifetime is short - must be at least 2 hours or set to Maximum settings.
          Try sending SMS from OneSimCard menu

           

           Problem with Receiving SMS:

          • Receiving Handset does not have enough free memory for incoming SMS.
          • Receiving Handset was turned off or out of the coverage area during SMS lifetime set on the sending phone - usually 2 hours.
          • Sender's SMS provider does not have an agreement with the receiving network.
      39. How To Use Questions
        • Is there a mobile app that will let me recharge my account and other services?

          Yes! Our myOneSim app for the iPhone devices will let you easily access many account services, such as recharging your account, checking voicemail, ordering discount voice and text plans, and much more. MyOneSim is available for download from the App store. Find more information in the Help section of your online account.

           

          DataMax SIM cards can't be managed by myOneSim app at this time

      40. How To Use Questions
        • How can I add airtime to my OneSimCard service?

          In order to add airtime instantly, simply register a credit card with us on our website.

          There are several ways to add airtime to your OneSimCard service.
          Automatic Recharge - recommended:

          1. Just log on to your account at www.onesimcard.com and set auto-recharge in the Recharge Menu. Funds will be added to your account when your balance drops below the threshold you set.

          From the phone using your credit card (Universal, Expedition and eSIM World only):

          1. a) From the phone dial pad dial 098YYYY*XX. Talk. YYYY = Last 4 digits of the credit card used last at OneSimCard.com. YY = Amount from 25 to 99 USD


           For example, if you need to add $50 and the last 4 digits of the credit card registered with us is  8654:
          You would dial 0988654*50 and press TALK. In few seconds you will get a confirmation message with  your new balance.
          * is a star character located on the keypad
          From the phone using 1SIM Fund:
           a) From the phone dialpad dial 098YYYY*XX. Talk. YYYY -  4 digits PIN you created in 1SIM FUND menu. YY Amount from 25 to 99 USD

           For example, if you need to add $50 and the 1SIM FUND PIN is  8654:
          You would dial 0988654*50 and press TALK. In few seconds you will get a confirmation message with  your new balance.
          * is a star character located on the keypad

          From the OneSimCard.com web interface:

          1. You must log in at www.onesimcard.com each time you wish to add funds.
          2. The minimum recharge amount is US $25.00
          3. Using Recharge PIN purchased from a dealer:

          If you purchased a recharge PIN from OneSimCard Authorized dealer, you can recharge your account from OneSimCard handset from OneSimCard - Add Credit menu. When the Add Credit menu is selected, enter the 10-digit PIN and press the Talk (Send) button. 

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