How to create a Internal access only ServiceDesk

[Charles]

I have attempted to set up multiple ITSM projects on JSM, but it appears they are not correctly configured for internal access only. I aim to create a company-managed project that permits only individuals from my company domain to access it. Currently, I must restrict project-level customer permissions, as there are many external customers on my Jira site who require access to other Service Desk projects. Additionally, I have disabled self-signup for the portal and emails. Is there a way to restrict this portal to internal users only without having to manually add them on the customers page?

Moreover, I tried a team-managed project that allowed me to set internal access to OPEN in the project settings. However, this configuration also allows users to access, view, and edit tickets freely, which is not ideal.