After upgrade to Pro my website is showing 502 Error and there is no active support to immediate fix

I am not sure what level of support you “expect” if it takes you almost a week to respond and even then you are not addressing the questions you were asked.

Lets start with the questions Matteo asked and additionally post your ticket number and when you opened that ticket.

Though, I can (almost) guarantee you already now that a 502 error will be something you need to fix yourself on server → Community Tip - Fixing Error 502 / 504: Bad Gateway