Very bad latency and high packet loss, but good internet download speed?

Hello everyone, I wanted to see if anyone else has had this issue recently with xfinity. I am on the 1200mbs plan and have been for a while now. However, recently I have had bad latency when it comes to gaming. For example I have tested packet loss and see fluctuating ranges from 10-85% at times. I sound robotic on calls (zoom, discord, etc.) During my testing I have realized that my internet speed is still consistently high. I am, at the time of typing this, seeing 500-600mbs download. Despite that speed, gaming has become unplayable online with the latency issues. I have read online that it may be the server that my modem uses when packets go back and forth but I am not educated in terms of such circumstances. So has anyone else experienced something like this?