Why can’t I see any services when logged in as a secondary user?

As secondary users, you need to access to primary account after login. Once login to the customer portal, click the Management Mode icon at the top right. Then, select the primary user’s name from the list to access their account.

Besides that, the view it depend on the roles assigned:

Manager Role – Can manage secondary users and assign roles and set up notifications, access My Services to view service lists and assist with name server changes, WHOIS updates, and domain ownership management.
Technical Role: Manage services through NovaCloud, Submit tickets via the Help Center.
Billing Role: View services that are expiring or have expired, Access My Services and the Billing & Payment sections.
Purchasing Role: Make purchases via the Dashboard or My Services section.
Visitation Role: Access My Services and the Data Center menu to submit visitation requests