Extremely High Latency Issues during evening (7-8pm) Every Day

Hi, I've been having extremely high latency issues for maybe 2-3 weeks with no resolution through hours of phone and chat support. I normally get 15-20ms of latency while gaming and while testing speed through an online speed test. After 7-8pm I would average anywhere from 100-150ms in both gaming and the speed test.

I've also had a technician come to my home and didn't find any issue. He said the only thing he thought it could have been was a modem issue, so I upgraded my speed and got a new modem. After this the issue actually got worse. Previously it would only happen every other day, and after I upgraded it is happening every day.

I'm getting sick and tired of these time wasting calls, as well as not being able to use the service I pay for the only time I am actually free. The issue isn't isolated as I'm experiencing it through my desktop connected via ethernet, as well as any other devices including my phone. My download/upload have remained good throughout the day, even during latency problems.

I have seen similar issues on the forum and decided that this would be the best way for someone to actually get me some help to solve this. I would appreciate anyone being able to help.