Anki unable to open collection file

Hey! Ever since updating to the new version, I’ve been unable to open my anki decks on the desktop app. It gives me the following message:
“Anki was unable to open your collection file. If problems persist after restarting your computer, please use the Open Backup button in the profile manager.”

However, when I try to load a backup, it gives me this message:
“Unable to move existing file to trash”

Furthermore, when I make a new user and open the desktop app, it says:
“Your Anki client does not support the new timezone handling yet. Please ensure your Anki is up to date.”
Even though I’ve tried both the 2.1.54 Qt5 and Qt6. This makes it so that I can’t sync with AnkiWeb anymore.

Could anyone help me with this?

That implies you’re loading an old version of Anki, which you may have lying around on your computer in a different location (eg \program files (x86)\anki) to where the latest version is installed.