Intermittent Internet service

Since there is apparently no way to directly talk to customer service anymore (unless it's an AI bot) I guess I'll try this.  For the last week or 2 my Internet with you guys has been very intermittent.  Sometimes it works fine other times I can't load anything.  I've run dozens upon dozens of speed tests from different sources and they all pretty much give me the same intermittent results.  One test I can see my full 150Mbps.  A second test I can't get above 15.  A third and fourth test I'm up to 40.  A fifth test in barely hitting 5Mbps.  And no matter what I do this doesn't seem to change.  Sometimes I can get consistent results for a short while, but then I'll start watching a stream and it'll start buffering or the image quality will change every few seconds.  Even simply opening a Google search can take a few seconds just to load the initial screen, whereas typically it's pretty much instant.  And I know the first things you're going to ask so yes I've tried rebooting both the modem and router.  I've even purchased a brand new modem and router.  I've played around with the settings of the router.  I've moved them around.  I've gotten closer. I've tried a direct connect.  And practically nothing changes.  After several days of testing (and the cost of a new modem and router) I'm not really any better off then I was at the beginning.  I've also checked on your troubleshoot section and every time it says there are no issues on your end but at this point I just don't see how that's possible.  Especially since just a couple of weeks ago I was having 0 issues, and even moreso now because I'm using a new modem and router so at this point it can't be anything wrong on my end.  And I know the speed can vary a bit based on what I'm paying for and I'm okay with that.  I just need consistency.  Jumping anywhere between 5 to 150Mbps does not make stable connection and it really messes with streaming services.