The reason for the issue is most likely missing the COREHR OBJECT PROFILE in the Object Profiles. To rectify this follow the steps below.
In the portal, go to Security and click on the User Management tab.
On the System Users widget, select All Back Office Accounts from the dropdown.
Find the user affected, click their three-dot ellipsis and select Manage Account.
This will get you to the next screen (Manage Back Office Account).
Click the Object Profiles tab and select/enable CoreHR Objects profile.
📌Note: Further account configuration maybe needed.