I can't make video calls

The phone is set to use the wrong network mode

Turn on automatic network mode selection.

1 of 8 steps Slide your finger down the display starting from the top edge of your phone.
2 of 8 steps Press the settings icon.
3 of 8 steps Press More networks.
4 of 8 steps Press Mobile networks.
5 of 8 steps Press Network mode.
6 of 8 steps Press LTE/WCDMA/GSM (auto connect), WCDMA/GSM (auto connect), WCDMA only or GSM only.
7 of 8 steps Press the Home key to return to the home screen.