Changed resolution in files but wont change in-game

Hey guys. Started playing about a month ago on a crappy old laptop. Changed all settings to lowest but still got meh fps. When i tried to change resolution it only gave 720p minimum, so i read up on how to change it in the config files using notepad. i also download a program called Cool File Viewer from the windows store. It worked at first as i was testing out some different res in practice tool and actually getting better fps. But then it stopped. Now, even if i save the changes, the game will only give the original res options and not then customized one. Coul i have messed it up? Should i re-install the game? Thanks for any help.
Report as:
Offensive Spam Harassment Incorrect Board