Hi,
That is correct by default an action group does not support sending alert notifications directly to Teams thus you need to use automation tool like Logic App for example. You should use the article provided to create. Once you create the Logic App action groups provide the capability to test it so you can test if the notification appears in Teams correctly or the Logic App is failing. Note that the example is for alert of type Metric alert. You should use common alert schema and there is specific payload for Log Alerts v2 to provide information that is specific for Log Alerts v2. Here you can find another example of Logic app with Teams notification or Outlook e-mail. where the information is send to e-mail.
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