Cannot send message to Slack via azure logic apps

Question

I am trying to send message to Slack with Logic apps. I set up the below settings.

1. Made workflow
2. Select [when a http request is received] as trigger.
3. Select [Slack - Post message].
4. sign in to Slack with SSO.
5. Test work flow

I guess slack didn’t accept access from azure logic apps as error sentence shown.

Could some one tell me the solution?

Thanks for your support.