T-Mobile USA review: T-Mobile techs in the store lied to me!

On Friday, July 31, 2026, I went into the T-Mobile store (664D) on U.S. #1, in Port St. Lucie, to take my old phone in to see if they could help me. Of course, they said it was the battery and that I would need to get a new phone. I wasn't happy to hear that there was nothing they could do with the old phone that I had. So, the tech tells me that I can get a new phone for free if I add a new line to my account. Well, I've been on the plan I was on for a long time and I really do not need a 4th line because there are only three of us. But he said the phone was free and the bill would go down if I added a 4th line. So, since now I needed a new phone anyway, I decided to get the free phone and add the line, which I did.
However, when my monthly bill came in there were charges for equipment for $40.00. This was in fact for the free phone. I called T-Mobile and they said that the credits would be coming but not yet. I waited for the next bill and called again. This time the person said that I should go back to the store and ask the tech about the free phone. This time they admitted that no credits are coming. The only help they had for me was to recommend that I go back to the store and ask the tech about the free phone. No one wanted to address the fact that I had been scammed at the store right in my face. Now I am paying $40.00 a month for the free phone and T-Mobile doesn't care.
I want T-Mobile to take back the free phone and stop charging me $40.00 a month for the equipment. I would like to be back on my old plan with 3 lines.