When a user can view Customer Item Codes page but unable to create / add a new one due to the error: "You need a higher permission for custom record type Customer Item Code to access this page."
The administrator should provide the following permissions below on the role:
1. Navigate to Setup > Users/Roles > Manage Roles.
2. Edit the preferred role.
3. Under Permission tab, provide the permissions with the corresponding level access below:
- Lists subtab > Custom Record Entries with FULL level
- Custom Record subtab > Customer Item Code with FULL level