Major billing problems

I returned a devise, pixel 7a, via UPs that was overheating , nearly bursting into flames  to the warrantee service center in Ft Worth tx per instruct. Having had problems with TMobile billing and services since starting the in January, I took the devise to a store, had them help me pack it   I took pictures of Jason helping me pack it the store and went directly to UPs in the same mall to ship it. ( May 11, 2024 ) When the bill came for the next month I found a charge of $478 + for " non returned phone" I called customer service after checking with UPS tracking and gave t mobile tracking info indicating the package arrived may 22at 1:45. The T-Mobile removed the 478 charge from the bill.  Today, I checked my bill, and found the $478 charge had again appeared. This time the T-Mobile rep indicated the package had arrived at the service cent but nothing was in it and they would be charging me for a " non returned phone". I've talked with UPS who indicated that T mobile needs to file a claim since they received the package and are claiming it was empty. 

I have spent literally hundreds of hours correcting St mobile billing errors, false claims, fraudulent sales info, and more. I tried believe it's time for the FCC to get involved, investigate the flip flam and for customers to start a class action suit because of St mobiles unscrupulous business practices, over billing and strong arming customers …

The replacement Pixel 7a also over heats and should be recalled before they burst into flames and hurt someone badly