After updating the Pro Theme I started getting 502 Errors when I click on the Widgets link within the Dashboard. That is the only place that is throwing the Error. I received an email alerting me to this error and it stated the following:
Since WordPress 5.2 there is a built-in feature that detects when a plugin or theme causes a fatal error on your site, and notifies you with this automated email.
In this case, WordPress caught an error with your theme, Pro.
So I searched the forum and I saw that in one 502 Error in the Forum you said to update the PHP code. I updated from 5.03 to 8.
It is still throwing the 502 Error only when I click on the link to edit Widgets.