Unable to change the priority mode of the game

Before I say anything I would like to specify my hardware. I am playing on PC with an Intel Core i7 8750H, 16GB of RAM and a GTX 1060.

I have been playing the game with low graphical settings and have been commonly getting frames below 30 FPS, this is because the game is running at normal priority mode. A simple issue to  fix. Open up task manager and switch the priority of the game to either above normal or high. No. When I attempt to change the priority mode of the game I can an error message reading "Unable to change priority. The operation could not be completed. Access is denied." (pictured here ). I have tried all the troubleshooting that I could think off, I have tried everything here (except for 6). I have tried running the game as an administrator to see if that would do anything, it didn't. I re-installed the game to see if that would change anything but that didn't do anything either.

So if anyone can help me with this issue, please please please please do. This is an incredible game and I'd really love to be able to play it with a good frame rate.