You have this issue if

• your game opens in a huge resolution
  
• you cannot change resolution through in game settings
  
• editing any config files did not help you

Here's how to fix:
1. Go to resolution settings on your monitor and pick the highest possible. Trove is for some unknown reason picking highest one, not the one you have picked as default. If you monitor is full HD, but option for 4k appears, go for it.
2. Run Trove, now you should be able to access settings, set it to preferred resolution, game should squish weirdly.
3. Close Trove, revert selected resolution, open Trove again
4. Now Trove should be running in a correct resolution