If you are willing to switch, tell your current carrier and sometimes that will light a fire under them to actually address the Support call. We had that happen recently. Internet went out. The issue was outside our house with the provider's line. They said they'd send someone a week later, so we pointed out it would be faster for us to switch providers, to which they replied, "We can't get there tomorrow but how about the next day?" We accepted and they actually did fix it in two days instead of seven.

I’m in the UK, we have a system for switching ISPs that is apparently relatively painless so I’ve started that process but it’s apparently going to be another 2 weeks before the switch can happen :(