When we transfer account ownership for PAID account, we uses IMS system to reset OpenConnect Link to a new owner ID. That process automatically delete old owner from the account members so that the previous owner has lost access to this account along with all of its keys.
In many cases, changing ownership does not mean removing the old owner from the account. At the moment, old owner needs to be re-invited and added back with required permissions, which is not a trivial task.
This is a side effect of current ownership change process and it can be considered as a defect.
I suggest to correct system NOT to remove old owner from the account but retain his membership with max permissions available as a member.
Then a new account owner can delete user OR modify user's access/permissions later if necessary.
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