Question 1

I can't call, text or use data?

Accepted Answer

The most important step to take when you encounter any calling, messaging or data issue (and you are sure your subscription and balances are in good standing) is to restart your device whether Android or iOS.

From time to time, phones may lose connection with their network.

Restarting forces the phone to reconnect, which helps with network and connectivity problems & restores the service.
If restarting the phone does not resolve the issue then try these basic troubleshooting steps 1 by 1 in the order listed.

Turn off your phone, Remove the SIM, softly clean it and reinstall it. Then power on your device and test the service again.
* If you have activated an eSIM, check the eSIM is correctly installed and reboot the device.

To make sure the SIM Card is installed correctly please check our related blog here.
To solve issues with the activation of your eSIM click here.
Turn off Wi-Fi & enable mobile data to ensure you're using the Tello network.
Go to the phone settings and verify that 4G/LTE or LTE is selected for the Network Mode and that VoLTE is ON.
Check under the phone settings that the latest software updates have been installed.
Uninstall downloaded apps such as calling apps; all blocking, launcher, and homescreen apps; and apps you downloaded around the time the problem started.
Tello can't support calls on other services such as Google Voice.
Perform a network reset which will erase any Wifi passwords your phone has stored:
- For Android:
  Go to Settings > System > Advanced. Tap Reset options. Tap Reset Wi-Fi, mobile & Bluetooth or tap on Reset Network Settings.
- Tap Reset Settings to confirm. *Note: If prompted, enter the current PIN, password, or pattern.
- For iOS:
  Go to Settings> General> Transfer or Reset> Reset > Reset Network Settings.

If the service is still not working properly after trying these steps then email us with the following information:

A description of the exact problem (incoming calls, outgoing calls, messaging, data etc)
The IMEI of the device
The phone number of the device
The troubleshooting steps you have tried
Any error messages (if any) that appear on your phone
The exact address where you are having issues. Please use this format: "Street Number and Name, City, State, ZIP code". This is because we need to check the coverage on your location.

Question 2

What do I do if I have a SIM card error message?

Accepted Answer

If your phone displays a SIM Card error message, do a couple of quick checks.

Firstly, ensure that you have inserted the Tello SIM into a compatible device - use our device checker to confirm this.
Secondly, ensure that your phone is unlocked. Contact the previous phone carrier (or phone seller) to confirm this. A locked device will not be able to use the Tello SIM.

Once you have confirmed the above, follow these steps:

Turn your phone off.
Remove the SIM Card.
Make sure the SIM Card isn’t damaged or you’ll need a replacement.
Insert the SIM Card back into your phone.
Turn your phone back on, follow any on-screen steps provided and your phone should start to automatically activate the Tello service.

Here’s a quick list of some of the most common SIM Card errors you may run into:

"sim not supported"
"network lock,"
"network unlock pin,"
"unsupported sim"
"SIM Lock"
"SIM Invalid"
"Network Lock"
"SIM Not Supported"

If you receive any of these error messages, your previous carrier may have enabled a lock or restriction to your phone and you will have to reach out to them to remove this lock.

Question 3

I cannot send/receive text messages. How can I solve this?

Accepted Answer

If you are experiencing issues with incoming or outgoing text messages, please check the next steps and settings to verify your device is configured correctly:

iOS:
If your iPhone is having issues sending SMS, it is possible this issue is related with the network settings:

First, go to Settings > Messages > Scroll down until you find the " Send as SMS" option. > Turn it ON.
Now SMS should be sent as regular text message and enable communication with non IOS devices and systems.
Also check your iMessage settings. Go to Settings> Messages > check the iMessage option is ON.
There you will also see the Send & Receive options > tap on it and then choose from the available options below “You can receive iMessages to and reply from.”
Go to Settings> Messages > Blocked Contacts > Verify the list of blocked numbers does not contain the contact of the person you desire to communicate with.

If the issue persist, please try the Reset Network Settings on your device to discard network connectivity problems:

Go to Settings > General > Transfer or Reset > Reset> Reset Network Settings.
The device will reboot. Teste the service again.

Android:

Most Android devices will have the RCS or Chat feature included. This feature uses internet connection for the SMS between android devices with the same option enabled. To check this setting:
- Open the Messages App ( make sure its the default app from your device and no third party applications)
- Tap o the 3 dot menu or Profile Picture Icon > go to Message settings
- Find the RCS/ Chat Features setting
- Disable the feature and test the service. If the issue persists, enable the feature again, wait for the verification and test the service one more time.
If the issue is for incoming SMS, please check the sending part is not blocked. Go to Messages > Tap the 3 dot menu or Profile Picture icon > go to Message settings > Spam & blocked> Select the contact from the list> Tap Unblock.
Perform a Reset Network on your device:
- Go to Settings > System > Advanced.
- Tap Reset options.
- Tap Reset Wi-Fi, mobile & Bluetooth, or tap on Reset Network Settings.
  Note If prompted, enter the current PIN, password, or pattern.
- Tap Reset Settings to confirm.

If none of the previous steps worked, please send us an email with the following details so we can investigate the issue:

Is the issue with incoming/ outgoing SMS?
Is the issue happening with one specific contact or all contacts?
Do you get any error message when trying to send an SMS?
IMEI number of your device

Question 4

What do I do if I receive the Voicemail invalid message?

Accepted Answer

First, make sure your Voicemail is properly set up:

There are 3 ways you can access the voicemail system:
- Press and hold the number 1 key
- Dial 123
- Dial your own Tello phone number
You will be directed to your voice mailbox and you'll have to initialize your mailbox.
If it was already set up, you will need to insert your password. In case you can not remember it, please note that you can Reset the Voicemail Password by dialing the code: #793# and follow the prompts in the confirmation message.
If the Voicemail was not set up, the recorder will prompt you to record your greeting, name and set up the password. Your voicemail should now be ready to use.
Once your Voicemail is set up, you can access it again by dialing any of the previous options.

In case your phone number is not recognized by the voicemail system and you still get an error of "Voicemail Invalid" please send us an email with the issue description or reach us via phone. You can find our contact information here.

Question 5

Why does my Visual Voicemail not work?

Accepted Answer

To use Visual Voicemail, you need to configure your device’s Voicemail application if it has one, or you can download a third-party Visual Voicemail app* (Android Only).

*Tello is NOT compatible with 3rd party Visual Voicemail apps except for the "T-Mobile Visual Voicemail" app or "My Visual Voicemail" app.

1. First, make sure that your Voicemail is configured. Check the detailed steps here.
To use and access the Visual Voicemail feature please make sure that:

You have a Data balance. (Visual Voicemail requires data connection to download the recordings)
You have WIFI off, Data ON, and set up the Visual Voicemail app using the password created when setting up the standard voicemail.
You keep Data ON to receive the notifications via Visual Voicemail.

If your device does not accommodate Visual Voicemail natively then regular Voicemail is the only option.

2. Then, according to your device, follow the instructions below:

For Android devices:
Most Android devices come with a default option for visual Voicemail that can be enabled:
Open the Phone app.
At the top right, tap More options.
Tap Settings. Voicemail.
Turn on Visual voicemail.

Alternatively, if you are using one of the compatiblle third party apps, you will need to follow the set up instructions in the respective application.

For iOS devices:
You need to open the Phone app > tap on Voicemail > click on the option called Set Up Now > Follow the prompts.

Also, please note that the Visual Voicemail feature will require you to use mobile data, so ensure your plan includes it and make sure it is turned ON, to use the feature properly.

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