Frustrated with trade-in and upgrade...

I am very frustrated at the moment. Have spend my whole Friday afternoon and Sat morning trying to upgrade my contract with no success. Been given promises that all will be sorted and no satisfaction. Everyone seems to have to escalate the problem but nobody sorting it out??? Did a trade in, my phone wiped...and that is what I am still sitting with!!! How can this be the kind of service that I have to deal with in this day and age. Thought the trade-in and upgrade service provided was simple and easy? If someone can help that would be great!!!!