T-Mobile USA review: samsung galaxy s4

I called my service provider, T-Mobile about my Samsung Galaxy S4 phone which had bent pins and was difficult to charge. They checked and said that my phone is still under warranty and emailed me a UPS label, to return the phone to their authorized repair center in Mesquite, Texas. I printed the prepaid UPS label and took my defective phone to my local UPS store in Paso Robles, California. They packed it and sent it to the authorized repair center at 4200 Samuell Blvd. in Mesquite, Texas on 11/27/2015.The phone was tracked and signed as delivered by UPS and received in Mesquite Texas on 12/2/2015. It is now 12/22/15. I have made several inquiries to T-Mobile customer service as to when I will receive my repaired phone back. I received an email dated 12/21/2015 claiming that I did not send my phone in to be repaired. I have tracking information and proof of delivery signed by Jenny Hernandez verifying that it was left at DOCK in Mesquite, Texas on 12/02/2015 at 10:00AM. The UPS tracking # is: 1ZRV91769098929769 The T-Mobile Handset order Research Request Reference is: [protected] I want my phone repaired and returned or a replacement sent. I have been without a working cell phone for a month and T-Mobile continues to charge my credit card $50.00 a month for service that I am unable to receive without my phone.