"This device cannot be transferred."

Somebody else must have switched Apple ID’s on the phone and associated the phone with that ID. You associate a device with an Apple ID any signing into another ID a on the phone and then by downloading purchased content with the switched Apple ID.

When you do what I have explained, you must wait 90 days before you can switch Apple ID’s again. You are 25 days into that waiting period. You cannot change this. You must wait the full 90 days.

No. You need to wait the remaining 65 days before you can change the ID associated with that phone.