Hi @AOG123
Mention function is used to get someone's attention in a channel conversation or group chat. For 1 to 1 chat, we usually do not need it.
However, if you have deployed the chat bot in your 1 to 1 chat. You could also use mention "@" to communicate with the chat bot. For more details about chat bot information, you could refer to:
https://learn.microsoft.com/en-us/microsoftteams/platform/bots/what-are-bots
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.