Many issues witn Xfinity billling, and technical support - 38 year customer

I have been a long time customer of Xfinity Comcast - even before they were Xfinity and Comcast.  In my neighborhood, we were AT&T Broadband in the old cable days.

I honestly can't figure this one out and am going to be contacting the customer loyalty department next.

After having basic cable and a different ISP, I signed up back in 2018 for the Xfinity Quad Play - Internet, TV with DVR, Landline and Home Security (monitored)

It was about $250 a month, including HBO and Cinemax.

Slowly over the next few years, it increased to about $320.  Not sure why, however that's not in scope for this complaint.  In addition, since 2018 I kept getting notices that my broadband speed kept increasing. Originally when I signed up it was 800Mb/s.  By the recent  billing it was 1.2 Mb/s

In April 2025, I started getting warnings that I am exceeding my 1.2 TB data cap.  First of all I had no idea there was a data cap - per the 2018 contract - there was never any data cap mentioned.  

The warnings told me I would be billed $10 for each 50GB over the cap up to a maximum of $100.

I immediately called in to Xfinity Internet support to request how all this extra bandwidth was being consumed.  They explained they can't tell me, its a privacy issue.  For example, they stated that I used 1.2 TB in the first few weeks of my billing cycle.

We have about 12 devices total on our Xfi Network.  In the past I could go to the Xfi application and see a breakdown of data consumed on a device by device basis.  This no longer worked, it only shows me total.

I explained to Xfinity support that they cannot bill me for something I have no visibility to.  They said they would take care of it and put me on an unlimited plan because I have 38 years of loyalty.

Low and behold, the next day my DVR went from 150 hours to 10 hours of service, many of my dvr recordings were deleted, 

I called in to support to complain about this and they fixed the DVR issue.

The following month, I received a bill for $500!

I had to call in again, and this time was really mad.  Apparently the previous rep reworked my entire account, cancelled my legacy Quad Play and put me into a completely different plan.  

The rep was extremely apologenic, however the new rep told me I am unable to get the legaxy Xfinity Quad play contract back as the previous change is permanent, and they can only work with current offers and promotions and to contact the customer retention department.  My new bill came and its still pretty high - over $350, and I noticed that there's other premium channels I didn't want.  In addition, my data is now 800 Mb/s instead of the original 1.2Tb/s

Does anyone in this forum know who I can talk to at a corporate level to get this straightened out?  I've been given misinformation many times and my account has been reworked to the point I don't recognize it anymore.

Thanks,
[Edited: PII]