iphone 12 is disabled/locked, how can unlock it without itunes or wifi being turned on on the iphone

My husband's iphone 12 screen reads iphone unavailable, and does not give an option to erase the it, he also turned itunes off on his phone a while back so i can't us that and his wifi wasn't turned on so I can't go through icloud either, he also turned off findmy so i can't reset it through that either. I don't know why he turned all that off but he did and I was wondering if anybody knew how to factory reset this phone so i can get it unlocked for him.