OPPO Find X5 Lite
It's not possible to use Wi-Fi calling
Solution 2 of 4: Your phone needs to be restarted
If your phone is slow or freezes, it might help to restart it.
If your phone is slow or freezes, it might help to restart it.
Press On/Off.
Simultaneously, press and hold the Top volume key and keep them both pressed until your phone restarts.