Service Address on my account is wrong

For some reason, the service address on my account has been changed. Last month's bill and all the previous ones for the past 10 years have shown the correct service address. This month's bill has a different service address. I have attempted to solve this problem twice over the past few days using the Xfinity chat. Both people I have worked with have not been able to resolve the issue, and took a painfully long with me on the chat. Xfinity is currently listing my actual service address (that I'm writing this post from, using Xfinity service) as a location that can't receive Xfinity service. This wouldn't be much of an issue except that Xfinity has sent me an email and my account shows that I should upgrade my modem - and the shipping address is wrong because the service address is wrong....