New Owner of my previous iPad (7th gen) is required to enter my Apple ID even after I removed device from my iCloud

The new owner of my previous iPad (7th gen), iOS15.2, is required to enter my Apple ID even after I removed device from my iCloud. iPad does show up under new owner's Devices on their iCloud! New owner wishes to change the passcode but we noted that under Settings, new owner's Apple ID (pictured icon, Apple ID, iCloud, iTune etc) is greyed out... Any thoughts??