Upgraded to 3.13.6 and visitor counts have dropped

Hi, I upgraded matomo to 3.13.6 and the visitor counts have dropped 20%. The matomo console often returns 504 error or the error message “there was a problem during the request. Maybe the server had a temporary issue, or maybe you requested a report with too much data.” , screenshot above. It has been been unstable for the last 3 days.

How do I resolve the time outs?