High jitter / Latency issues while playing GPS games online

I got xfinity installed in Feb and in June I started having issues with internet while I have been playing online competitive games like Counterstrike 2 I have been facing constant lag and jitter issues everytime and everyday.

Been playing on wifi since day 1 and didn't have any issues before no changes were made to surroundings or connection.

Because of that I have been playing on my Phone Tmobile Hotspot which doesn't give me the issues I experience on Xfinity.

2 weeks ago, a technician also came checked the line and router which were fine but still the problem hasn't been fixed. 

If this goes on, I might have to switch my provider.

Is anyone else experiencing the same issue?