Your voicemail is a familiar tool for getting the most out of your calling experience in Teams. To access your voicemail, go to Calls 
> History and then select Voicemail.
...
Call someone back by hovering over a voicemail and selecting Call
or by selecting More actions 
and choosing Call back 
.When you select a voicemail, you can review and access details and other information—all on the right side of Teams.
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