Hi there!

We don't necessarily use the word "sync" at Zapier because that's not quite what we do. This may address what I think you're trying to do: https://zapier.com/help/troubleshoot#two-way-syncing

Out of curiosity, what were you looking to sync between the two? Was it when contacts are added to MS Teams? I ask because the only triggers available at the moment are (https://zapier.com/apps/microsoft-teams/integrations#triggers-and-actions):

New Channel
Triggers when a new channel is created within a team.

New Message Posted to Channel
Triggers when a new message is posted within a channel.