Redeem code suddenly associated to the invited email

My company has been sharing the redeem code to the company domain email address and allow staff to redeem the app with their personal Apple ID.

However, we found that the redeem code is failing and claiming the Apple ID doesn't match the one associated with the invitation.

I cannot find the documentation for this change, may I know if this is something permanent?

Redeem code suddenly associated to the invited email
 
 
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