Since it's a company domain email addresses you need to use Business managed appleIDs. Ask you IT department to take care of it ( https://business.apple.com ). But then I have another problem:
Once this kind of AppleID created and I am inviting my developer to the appstoreconnect , but he does not receive an invite since this kind of AppleID does not support email capabilities. Didn't figured it out yet ....
andriest
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