Hi @surya kumar
According to the Microsoft support document, tags are not supported in private or shared channels. One of the possible reasons for this limitation is that some people with that tag might not have access to a private channel, and therefore they would not receive the notification or see the message. Another reason might be that tags are designed to be team-wide, and private channels are meant to be exclusive and focused spaces for collaboration within a team.
Meanwhile, to get this feature more quickly, we recommend you give the feedback in Teams UserVoice. Many features of our current products are designed and upgraded based on customers’ feedback. With requirements like this increase, the problem may well be released in the future. Thanks for your understanding and support.
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