My wifi calling is not working. If the phone is on wifi when a call comes in it snaps and pops then drops the call. Sometimes it doesn't ring and goes straight to voice mail. The stupid RTT thing pops up on both my phone and the other person's phone during a call and won't let you out even though that function is turned off. I have to keep the wifi off if I'm expecting a call. I know it's not the modem I have. So it has to be the phone.
google has a free phone number and service app. try using theirs and see if you have the same problem. maybe that can narrow it down alittle. I think it might be a cable service provider issue.
Have you tried clearing the cache partition on your phone?
- Turn off the device.
- Press and hold the Volume Up key and the Bixby / Power key.
- When the Android logo displays, release both keys.
- An 'Installing system update' message may show briefly before the Android Recovery menu options appear.
- Press the Volume down key several times to highlight Wipe cache partition.
- Press Bixby / Power key to select.
- Press the Volume down key to highlight Yes, then press the Bixby / Power key to select.
- When the process is complete, Reboot system now is highlighted.
- Press the Bixby / Power key to restart the device.