Hi @Starlite Thanks for your report 
It will be tricky to identify this issue as Guild Wars is over
Can you please let me know
- How long was Gems of War open before this happened?
- What was the last thing you did in the game before this occurred?
- What game mode did you play before this issue?
If it happens again please try these steps to resolve it, and check if it fixes after reach point
Close/reopen the game
Try completing another battle
Reinstall the game