Xfinity mobile charges after I quit

I quit Xfinity Mobile in 2024 October because you said you would refund me on a three-way call with Samsung and then later denied the phone call and the refund but I proved the phone call and got the refund. 
However when I quit you kept charging me and when I called about it March 17th 2026 you said we can refund 6 months it doesn't go back any further than that, but it goes back to November of 2024. On a phone call on the 19th of March 2026 you said you would refund the rest and then when I saw that you did not I called back on October 26th 2026 you denied that that you said that but then the first caller said we can refund you half of that or around $300 and I said well it goes back further than that so they gave me a supervisor who said he could not refund anything at all.

Policy you know, very convenient. So I got three completely different stories from Xfinity. Like before when I was with your Xfinity mobile service. 
I'm disappointed that a company that I thought was good has treated me in a dishonest way acting as though they haven't made statements that they have made on recorded phone calls so I'm wondering where I should go with this. You should do what is right and refund the rest of money you unjustly charged me. 
There was a time I thought you were the very best company to have internet and mobile with but I was very wrong. 

I would appreciate a response maybe you can tell me besides using your policy as an excuse as to why you won't give me the money that you unjustly charged me. Thank you very much.
Sincerely, John [Edited: "Personal Information"]

I don't have an account number because I quit you but here's some information. 

Address [Edited: "Personal Information"]

Phone number [Edited: "Personal Information"]

I reopened the case with direct Express, dispute number [Edited: "Personal Information"]