How to Escalate the Ethernet Issues...

  How can the process of escalating an xFinity internet issue not be handled problem by problem of the standard Xfinity Support Team?   
It's happened to me within the 3 years until now, my internet package was 1,200Mpbs megabits download speed, but the speed only reached 800Mpb to 900Mpbs. Within three years, I kept calling three or four times to complain about this issue, I have had multiple technicians from Xfinity service teams come to my home over the past 3 years and still cannot get my internet working reliably day to day. They requested I switch my modem twice to Xfinity Modem/Router and check the box outside and still no results. Also, I had to upgrade the Ethernet Cable to 6A. Last week on 8/16/2024, we upgraded the Plan/package from 1,200Mpbs to 2,000Mpbs with the latest xb8 Modem/Router, nothing improved the download speed of 900Mpbs is still the same problem. 
  Then I called the Xfinity Support Team to explain the issues, well they promised would send the best "supervisor technician" to diagnose and fix the problem caused about 3 years ago and until now. We had two technicians come by on 8/22/2024 and state the issue was the wiring on the pole that connects to our home and this is another team. Also, another technician found out the "Main Box Network" outside had a problem with the weak signal and needed to be repaired. Also, our neighborhood had the same kind this problem. Until now, I had no callback or Text update about this issue. Here we go again, same drama, the Technician disappears without fixing the problem, except cost me lost wages and time. Is there a specialist Team and a Supervisor Technical that understands the System (Main Box Network) and can pinpoint the problem? 
  Please, we have been loyal customers for too many years and has become impossible to work from home with my family working online shops to get internet. We need help!!! We need help!!! We need help!!!