Hi TheOrangeGecko! The issue with not being able to click buttons is usually due to the game thinking it's in a different resolution than it actually is, so the hit boxes in the menus are offset from what you see on screen. You can try deleting your settings file to reset everything to default. It can be found on your PC here: C:\Users\YourUserName\AppData\Local\ShopSim\Saved\SaveGames
If you're having trouble finding it, reading this post (and its replies) should help: https://itch.io/post/128793/view-in-topic