This may be due to the affected user not having sufficient rights to access the specific area of the Admin tool.
Use the steps below to confirm if the affected user has administrator level access.
In the Admin Tool, select User Accounts.
Enter the affected user in the Name Like search box and select All users from the User Filter drop down.
Double-click on the affected user.
Expand the Administrator Application Security section by clicking on the green arrow.
Click on Change next to User Level and select Administrator.
This will display a list of the modules available to the user and the level of access.
Typically, this will be a choice between Basic and Administrator.
📌 Note: If you can only see the Basic option, then you will need a user with Administrator access to give administrator rights to the affected user using the steps above and selecting Administrator.
If there is no longer an account with administrator rights then please raise a new case online.