An administrator is configuring a new Cisco Webex Hybrid Message Service deployment, and the Expressway-C Message Connector is successfully registered in the Control Hub. After the server information of the IM and Presence server is added to the Expressway-C, an error "Connectivity to IM and Presence AXL Service could not be established" is displayed in the Control Hub. The Cisco AXL Web Service is enabled on the IM and Presence Service publisher, and the main administrator account enabled for AXL API permission is being used.
Which configuration change must be made to resolve this error?