Grafana MSTeams Webhook not working

Hi All,
I am trying to connect MS Teams with Grafana using webhooks. I have the webhook URL and I tried using a Powershell script to push a demo payload to Teams using the same webhook.
[Invoke-RestMethod -Method post -ContentType ‘Application/Json’ -Body ‘{“text”:“Connector Test”}’ -Uri]

However, when I use the same webhook details from inside grafana and send test,I get an error.
[t=2020-03-06T12:33:34+0530 lvl=eror msg=“Failed to send alert notifications” logger=context userId=1 orgId=1 uname=admin error=“Post dial tcp connectex: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.”
t=2020-03-06T12:33:34+0530 lvl=eror msg=“Request Completed” logger=context userId=1 orgId=1 uname=admin method=POST path=/api/alert-notifications/test status=500 remote_addr=[::1] time_ms=24831 size=48 referer=http://localhost:3000/alerting/notification/5/edit

Configuration -

  1. Grafana - Grafana v6.5.2 (742d165)
  2. Data source - MSSQL