Refurbished iPhone 6s Plus is locked to previous owner all of a sudden

I don't know exactly what happened but when I reset the phone this time around activation lock came on and it doesn't State anything about the email or anything that was used for this old Apple ID from the previous owner but it needs it in order to go into the phone past setup mode. How do I go about this exact problem I've legit have purchased the phone. It will not accept my Apple ID whatsoever