T-Mobile USA review: Customer service

On October 6, 2023 I visited the Tmobile store located in Parkchester Bronx, NY where I purchased the iphone 15 and I requested to trade in my iphone 12. They did not have the iphone 15 in store so they informed me they would ship the phone to me. I received the phone on October 11, 2023 to my home. Because I did not have my new phone they counted my phone as a deferred trade-in. When I received the new phone I went back to the Tmobile store to return the iphone 12. I was informed that I would not be able to return the phone to the store. I was not shipped a return label so I contacted Tmobile and was informed by a customer service representative who informed me they would be contacting the store to return the phone. The representative stated that she would contact me again to confirm. I contacted Tmobile two days later after not receiving a call back who states that they have to mail me a shipping label that I have to print out on my non-existent printer. There has to be a streamlined process to returning trade-ins to the store. Additionally, I will have to find a printer and go to the post office to return the phone so they do not charge me 700 dollars for the trade-in.