Google Admob upgrade 403 error

[d...@effectualgaming.com]

Our new abmob account is not working properly from last 3 months. When we click review import data summary or new admob it shows 403 error. See the attached screenshot. We are not able to add new apps in legacy admob. Does anyone knows how to solve this issue? Sent lot of mails to support on the following link. But no one is replying from 2-3 months 

https://support.google.com/admob/v2/contact/account_upgrade_issues