need help speaking to a manager

I have been a long time customer and recently had my phone fail on me. I went through a warranty exchange and the refurb (#1) phone they sent me had someone’s information still on it. It had login information for this persons Amazon and Spotify account!!  I was able to see all of his stuff.  I called to report it and was promised a new phone by a “supervisor“. When that phone arrived it was another refurb phone (#2) of lesser quality then the one they sent me the first time! This time I called again and spoke with a guy named Dak who promised me he would help me. Over a week and a half he kept promising me he was going to get me a new phone but then finally told me his upper tech people rejected it and I should just wipe the phone and start over. So I called and waited till I got a US call center and spoke again with another supervisor in Georgia and she told me I had to but a new phone or take a refurb. Those were my only options. I was not happy but she kept insisting. So I finally relented and agreed to another (#3) refurb phone. But asked if it could be a grade A refurb. She said yes!  Well, when it came, it was a grade B!  THEN, I got it all set up and THE EAR SPEAKER DOESN’T WORK!  It’s all muffled and garbled and staticky!!!!  I can only listen to a call through headphones or on speaker! Can someone help please. I don’t want to leave Tmobil but I will if they don’t make this right!