Lost my encryption key. What can I do?

I lost my encryption key for the desktop app on my laptop. I’ve got the keys for my mobile devices and the web app, but I lost the one for the desktop app.

Is there some way to erase that profile in order to generate a new key? Is there a file or folder on my hard drive that I can delete in order to initialize a new login profile?

I don’t want to delete my account, because it’s the primary admin account.