Error - Please reinstall your game due to missing things

Hi!

A couple months ago, I downloaded the [Name removed] DLC unlocker, now, halfway through this process and I thought, I probably shouldn't be doing this and stopped. I've now deleted and uninstalled it and cannot load up my game. I've redownloaded it, removed it from my account and added it back, and nothing is working. It keeps saying I'm missing stuff.

I heavily regret doing this as I haven't been able to play for months.

If anyone has ideas to fix this, please help