Xfinity mobile agents messed up my mobile orders, Offers and activation

Hi,

I have port in my number and my brother number to xfinity recently and trade-in for my wife. ordered 3 phones first as per xfinity agent gave me the 500$ off on 2 port in phones and 550$ off for my 1 trade-in on Nov 26th,2023 as thanksgiving offer which end in Dec 5th, 2023. so they have ordered 5 phones instead of 3. all phones 5 phones I have received on Dec 4th. I have called them for return and trying to activate, they port in my number and activated on wrong device by mistake. they cancelled it and I have lost my number and end up returning only one phone instead of 2. The returning process for another phone is still in process and never provided me return label. I have end up calling xfinity agent from Dec 5th to Dec 13th everyday 2 hours on the call and never get a solution. finally they ported my number to one device and mentioned there is no 500$ offer for all the devices which made me port to xfinity. so I have end up without phone number for 5 days and mental stress not able to return the Phone. Now they are saying you are not eligible to return the phones because 14 day return period is expired(received order on Dec 4th, so they don't care when you receive) and also no 500$ off. in order to get the 500$ off you need to return all the devices and order again. so if I do that I will lose my Phone number again. so I have wasted my time, big stress, no 500$ off which is made me to port to xfinity and got the huge bill 345$/month and paid around 877$ for initial order(able to return 1 and get the refund).  I'm trying to contact the supervisor but I have failed and had a phone call with around 10 agents. every time if I call an agent they will mess up and no resolution, need to explain from scratch, fake callback promises. so it's minimum 2 hours call. what should I do