App Store shows outdated Apple ID and doesn't allow entering password after update to Catalina
I updated my iMac to Catalina. After this update the App Store shows newer versions for several applications. When I press Update All, a password dialog shows up. The password field shows a greyed out Apple ID. Normally I would be able to enter a password in this field, but the App Store blocks entering characters in the field. Probably because the Apple ID that is shown, is not the Apple ID I'm logged in with. It's an outdated Apple ID that I'm not using anymore for a long time now.
Logging out and in of the Store doesn't help and I cannot update any application. Also when I click an individual application (and not the Update All button) the outdated Apple ID shows up. Even with applications that are purchased with my current Apple ID, as listed in the Purchase History.
Any ideas how to fix this? Thanks!
iMac Line (2012 and Later)