Hello @Hinal Halvadia As of now you can not revoke refresh token for specific app such as outlook. You have to revoke the refresh token for a given user account.
You can use Azure AD Graph to Invalidate all refresh tokens for a user using below Graph Call:
POST https://graph.windows.net/myorganization/users/{user_id}/invalidateAllRefreshTokens?api-version=1.6
Or you can use Azure AD Powershell for this purpose as well:
Revoke-AzureADUserAllRefreshToken -ObjectId "<user_object_id>"
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