Hi Hassen, 

I see that you opened a ticket with our support team and this is being addressed there. I'm going to mark this feature request as completed because our connector works if business_management permission is not granted. There is logic in the setup test and also in the sync logic itself. If we do not have this permission we will skip all “business“ fields.

Your specific connector caught a bug in our logic because we just check if there is this permission present in the token, and if it is we send requests with all business fields. Your specific connector has a token with business_management permission. However, if you check the granular scopes you will see that it is not applicable for all objects and it is not applicable to the ad account the connection is attempting to sync. We've now addressed this edge case by checking the granular scopes.

Cheers, 
Luke