Lolskd

Hello, I'm not sure what happened, but when I tried installing an app, the error in the title popped up and I don't know how to fix it. I looked at a forum where they were talking about it, but I don't know where to access any of the things they were talking about. Can anyone let me know step by step how to resolve this issue? I'm on IOS 14.8.1, not jailbroken, and I'm using a PC for sideloadedly. Any help is appreciated, thanks.