T-Mobile USA review: T-Mobile cell phone account

I switched service providers from T-Mobile to Verizon in 2021. I immediately tried to port my numbers and one number on the account could not be ported due to discrepancies in my account. While I had an active line, I was told that the IMEI numbers did not match T-Mobiles records and the phone could not be unlocked. As retired military, I did not want to change my number to one where people I haven't had contact in awhile could not reach me. After numerous calls and great frustration, it appeared the IMEI number belonged to an iPad and I had never registered an iPad to the T-Mobile account. It actually took OVER TWO YEARS to finally port the number. The account was inactive during this time and I was PROMISED that it only needed to be reactivated at the time when the transfer took place - which should take about 10 minutes. I was sent from pillar to post. When I first called to request a transfer PIN number, the representatives acted like they had no idea what that was. Eventually, the requests could not be handled over the phone and I was sent to Verizon stores, where the staff could not help me. After visiting nearly a dozen Verizon stores in more than one state, I finally found someone to help me in late 2023. Despite receiving no service and being unable to close the T-Mobile account due to my phone number being held hostage, I received a bill. I called to explain that the account was only still open (although not active) due to the unwillingness of T-Mobile to provide proper assistance in porting my number. I spent untold hours and many people could not contact me during this period. A five minutes processed persisted for several years. Now I am receiving dunning letters, even though I even sent a certified letter to headquarters, to which I received no reply. As a disabled veteran, I am shocked at this treatment by T-Mobile.