When trying to upload an App to iTunes connect in Xcode 8.3.3, I get the error:
iTunes Connect access for \"Team-Name\" is required. Add an account in
In My case none of the above solutions worked,
I have an access for both Developer account and iTunes Connect account, but I faced the same Issue.
The only option worked for me is updating my MAC OS before it was 10.13.4, after update to 10.13.6 the problem was resolved. Hope this will help to someone.