Extremely disappointing service since the “upgrade”

I have been using Axxess for my LTE internet service, but since their so-called upgrade, my internet connectivity has become extremely unreliable. I have already raised the issue with Axxess twice. Instead of properly resolving the problem, I was instructed to change the APN settings. I followed their instructions and even rebooted the device, but the problem still exists. What makes this particularly frustrating is that I am paying every month for a service that I am simply not receiving at the standard I am paying for. The service was working better before the “upgrade” than it is now. An upgrade should improve the customer experience, not make the service worse. At this point, I am extremely disappointed with Axxess and the way this issue has been handled. I need a proper technical investigation and a permanent solution, not another generic instruction to change settings. If Axxess cannot provide the service I am paying for, then they need to seriously reconsider their offering and customer support. Very disappointing experience.