incomplete setup of a new iPhone 11 pro

when I set up the new phone through the migration utility, it shows complete transfer and only few steps to finish the set up

however, when I press continue, it turn to wifi selection. Then I press "next" , it returns to

"Hello" screen. I can open it by face id sometimes, passcode needs sometimes instead.

Every time it return to the screen mentioned above.

I tried to connect to iTunes and try to reset but it asks me to turn off the Find My first

I cannot restore old back up for showing the phone is not yet set up

Why is that?

Thanks

Regards

Nelson