Cant press on anything when playing a game.

When im playing a game like roblox, fortnite, or minecraft, and I try to open up discord, I cant open it. It wont let me press on anything like my apps or taskbar. I can only use my keyboard. This happens 50/50 times and it wont let me press on anything even after I close the game. I have to restart my pc to be able to press on things. I think its because of the boost things in razer cortex, but I dont know. I only use razer for razer cortex.