over charged after re negotiating contract

I called in May 2025 after my bill increased suddenly, and spoke to an agent who offered a lower rate. My auto pay has been charged the full amount since then. I called back in June and was told my rate adjustment was pending, but he assured me he got it approved. I received an email yesterday still showing the full amount due for my July bill, so I chatted with an agent who told me I was actually owed a credit, so she fixed it and I would receive a new invoice in 6 hours. I didn't receive the email, and when I log into my account today, the full amount is still showing as due. I chatted with an xfinity agent today and he gave me the run around again, saying the rate adjustment is still pending and stuck in processing status. He assured me he fixed it once again, however I am ready to cancel and switch to another internet provider. How can I get this resolved and out of pending status? I would also like a new bill emailed to me with the correct amount due.