Extremely high latency spikes every single night past 6pm

Every single night my latency when gaming or even just watching shows spikes extremely high, usually over 1000 to 5000 ms latency and pretty much causes the internet to be unusable. Techs have came out 3 different times and checked the router, and ran completely new coaxial cables inside the house to the street, and even new cables outside the house and the issue has not been fixed. I was told during my last appointment that the problem is with the nodes in my area getting congested during peak hours and its been weeks now with no change or fix. How can i escalate this issue to get my problem looked at and fixed. Thank you for looking into my issue.