Google supports everything for your Google account, signing in, and all its services.
If you need to get out of a jam with your account, Google can fix locked accounts, username or password recovery, and other issues. Contact Google. T-Mobile can only make sure your device can connect to the Internet to use Google services.
- In the web browser, open a few web pages to check your Internet connection is loading. If it's not loading, go see No Internet instead.
- Check G Suite Status Dashboard for any Google disruptions or outages. Those can prevent your sign in.
- Sign in to your Google account from a computer to test access. If you can't, the problem is definitely Google, so contact them.
- Restart the device.
- If you have 2-step verification enabled, be sure you're entering the security password. See 2-Step Verification - Google Account Help.
- If you still cannot sign in, perform a master reset on your device. (Visit your Devices page, and use the Device Reset page for help.)
- Try to sign in to your Google account again.
- If you still cannot sign in, create a new Google account or contact Google.
Visit Google for password recovery at Change or reset your password - Google Account Help.