Can't change resolution

Hi guys.
I was wondering of anyone had a solution to this problem?
My game won't change the resolution no matter what i do.
I've already checked that the game is running on my graphics card but i still can't change it.
i also have a couple mods installed but on other computers with the same mods the problem doesn't occur.
sorry if i have bad grammar, english is not my first language.
- Video of the problem.

Thanks in advance.