YouTube not playing in Safari on macOS after internet upgrade

Ever since we upgraded our internet service (better speed) I have had problems with playing content from YouTube on Safari in macOS Catalina.

For about 8 of every 10 videos from YouTube I get the following error:

I have tried all of Google's suggested fixes and all didn't work except for playing in Chrome. So I figured this is a Safari issue since it plays fine in Chrome. The suggested fixes were: restarting the browser, restarting the router, restarting the computer, update browser to latest version, use Chrome.

Can you please help me fix this issue and watch YouTube on my iMac instead of going to my iPad.