Free phone Not free

I upgraded my phone via chat a couple of months back and was told I had  a choice of the S24 or S24 + for free. Of course I picked the S24+ who wouldn't  pick the better phone. I have been charged 11.04 a month for 3 months now. FYI I do have a screenshot  of the chat where the rep says either phone is free. I have called and they were going to get back to me but never did. 2nd month I get oversee twice they don't understand  but I got a credit of 11.04 and was told they are still working on it. Today I get my bill I'm still being charged. I called and spoke to one rep who sent me to a supervisor  who offered me 100.00 , I have 21 more payments at 11.04, that doesn't  equal 100.00. I refused  the offer and told her to send it to a higher up. Supposedly someone will call me in 24 to 72 hours.  I won't hold my breath. I have been a loyal  customer  for over 20 years but they don't care.