Hello, i updated a new version for my app, but after that i lost all connection with my app, when i am trying to check it by link i get error "app is not available in your region", but in my app store connect settings i allow all regions for this app. Also i tried to change regions on my phones and it is no effect, whats wrong?

I can not add myself to a sandbox testers. I see the "+" button But the problem is i am trying to add myself. I already have myself there! I tapped "+", when i earn all fields it says user already exists. Whats wrong? How can i. test my purchase??