I strongly recommend to review all steps documented in the manual, Supported versions, ports, roles, permission, system clock synchronization, etc.
If data is indexed, search "index=ontap*" should return events at least. If there are, ontap_admin role is not assigned to admin user.
If data are not indexed, check firewall or network proxy server etc between the search head and DCN.
If this cannot help,
1. File a Support case if you're an Enterprise customer.
2. If you're Community user, post more information such as versions, topology, error/warning message, what kind of troubleshooting you already did and what you could or could not validate