Xfinity Account Cancelation Nightmare

Has anyone else dealt with this? I switched plans with Xfinity and was sent new equipment. We’re still at the same address but for whatever reason, they opened a second account for us. I called immediately after getting the new equipment delivered and had the old account cancelled. So I thought. I was given a confirmation number and told to send the old equipment back which I did. I noticed about a week later the old account was still showing on my customer portal. Called back and was again assured the account was cancelled and I wouldn’t be billed. Fast forward to this past weekend, I receive two bills (one for the old account and one for the new). I called again and was told the first cancellation didn’t process correctly and they’d reprocess it and waive the bill since it was their mistake. Now it’s been a week and the account is still active and the bill is still showing. I contacted another rep this morning and was told I needed to pay the bill and just wait for a refund and they would try processing the cancellation again. I’m not paying for something that shouldn’t have been active in the first place. I requested to speak with another agent who told me the same thing. I’m so frustrated. This has been a whole month now of trying to just get an old account closed and it’s like no one can help me. I’ve been given multiple cancellation confirmation numbers, multiple “cancellation” dates, and none of them have proved to be true. Anyone have tips of how to actually get an account closed? Thanks.