In this case we may check the ECC output/input of Shazzam. If there is no actual ports being scanned by Shazzam, the according IP Services records (for ports) may have been deleted by mistake. The Discovery port probes may show sys_ids instead of IP Service name as shown in attached screenshot.
We should then check the IP Services (cmdb_ip_service) table to verify if this is the issue. There should be 44 records in IP Service table on OOTB instance. Please see attached screenshots. The solution is to restore the default IP Services records by importing them from another OOTB instance.