Does anyone else have the same issue in your organization?
Have you tried to create a new private channel to see if this issue can be reproduced?
Is this account external or internal users?Private channel is a special channel that allows you to participate with your part of team members (from the team) and collaborate. Only these group of members will have access to a private channel and no one else in the team. Please note that to invite guest user, you need to work with your IT Administrator to enable guest access policy from the team admin center.
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