3 unsuccessful unlock request

I have submitted 3 unlock requests for an iPhone 8 I paid off about a year ago. 2 of them were submitted as they instruct us to do which is through the online portal. One of them was submitted through one of the customer service reps through the online chat. All three have been unsuccessful. The gentle through the chat insisted that the phone will be unlocked and there will be nothing for me to do beyond that point. He gave me a refernce number. A day later(sat 27th) I get an email stating my request could not be completed. I reach out to the customer service dept. through online chat, and that rep states that it was denied because I didn’t verify a email. She again took me through the process of submitting the request for me and providing me with a refernce number. Again she ensures me that this will take care of the problem and that I only need to watch for a email which I never received the previous 3 times. She declined to escalate this issue for me stating there was no way of her doing so. I would like for someone to help me get this issue resolved ASAP.