can't sign out of Apple ID - iMac

I am selling my iMac (just upgraded to Studio) and need to clean up before selling. Here's what happens when I try to sign out

iMac 27" late 2015, Intel i7

Monterey 12.7.5 - this is latest I can upgrade to

Restart

System preferences>Apple ID>Overview>Sign out

Do you want to keep copy of iCloud data on your Mac – uncheck, then enter Continue

Enter Apple ID

Enter Password

Enter Mac Password

Do you want to merge Safari with iCloud? Enter Don’t Merge

Allow Find My Mac to yse location of this Mac? Enter Not Now

System then either spins endlessly or just returns to original state like no action was taken

Around and around