Adjusting alert preferences for messages, mentions, and activity within Microsoft Teams
Dear Kristy,
Since the problem affects only one user across multiple devices, it is more likely related to that user's installation record, identity mapping, stored conversation reference, or an app policy applied to them, rather than the Teams client itself. Uninstalling and reinstalling on additional devices is unlikely to resolve a server-side mapping problem.
To help narrow this down, could you share a few more details?
- Can the affected user open the app and send a message to the bot?
- If so, does the bot respond?
- Are the missing notifications proactive bot messages, activity feed notifications, or channel messages?
- Does the affected user belong to the same Microsoft 365 tenant as the working users?
- Is the app installed in the user's personal scope, or only in a team or channel?
- What status code and response body does the bot receive when it attempts to send to this user?
- How are you identifying the user, by Microsoft Entra object ID, Teams user ID, email address, or a stored conversation reference?
The most useful detail here would be the exact status code and response body logged when the bot tries to notify the affected user. That alone will usually point to whether this is a stale conversation reference, a permissions problem, or the user simply not being resolved correctly. It would also be worth checking whether any app permission or setup policy in the Teams admin center differs for this user, as that can silently prevent an app from functioning even after a successful install.
Looking forward to your reply, and I will do my best to help from there.
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