I can't make video calls

The phone is set to use the wrong network mode

Turn on automatic network mode selection.

1 of 9 steps Slide your finger down the display starting from the top edge of your phone.
2 of 9 steps Press the settings icon.
3 of 9 steps Press the Connections tab.
4 of 9 steps Press More networks.
5 of 9 steps Press Mobile networks.
6 of 9 steps Press Network mode.
7 of 9 steps Press LTE/GSM/WCDMA (auto connect), GSM/WCDMA (auto connect), GSM only or WCDMA only.
8 of 9 steps Press the Home key to return to the home screen.