Tried to launch an application I’ve been using for the last 7.5 years and last week with NO problems, Today I got this:
I tried to sign in as instructed but then got this:
I immediately jumped through Apple’s hoops and changed the Apple ID password just in case.
I’d guess the login problem is related to the iMazing problem discussed here earlier and a now fixed Apple Configurator problem. Apple seems to be making changes to its app login infrastructure.
I’ve occasionally seen things like this, especially if the computer has gone a few months without a reboot. Rebooting often helps.