Can't speak with a live agent anymore

I've spoken to 5 different agents re-explaining my case about how they overcharged me on my billing statement. The last agent I spoke with had a deal to help resolve the overcharge issue by getting a retroactive unlimited plan. After over 3 hours of repeated lines and discussion, and right as we were about to finalize the agreement, my internet disconnected "randomly." Now when I try to speak to a live agent again, I either get an error saying I can't connect right then, or I'm stuck 2nd in line for over an hour, or it says I'm connected to a live agent but no one says anything??? I can't access anything on my account either. When I try to sign in, the website crashes. When I sign in on my phone, it says "Error: Sorry, this isn't working right now" (or ever...). So I don't even have control of my billing anymore. Wtf. Also, when I scroll up in the Xfinity Assistant chat, I noticed some of the messages were deleted??? Noteably, the ones where I'm asking them to take accountability for a mistake they made. It seems very suspicious, and now there seems to be no real way to reach a real human being who genuinely is going to help. This is my last option before I go complain at an Xfinity store. Can someone for the love of God please help me?

I was speaking with an Xfinity supervisor and they were about to help me set up an unlimited plan with a promotional discount starting in May to waive the mistaken billing overcharge on my courtesy month. I just want help completing this process.

[Edited: Personal Information]