One user cannot see Transactions but others can - why?

Summary:

I have a support ticket where one user cannot see any Transactions via Receivables -> Billing -> Manage Transactions.

Content (required):

User goes to Receivables -> Billing

Chooses Business Unit from top left, then goes to Tasks -> Manage Transactions:

Run a search - nothing returned:

Yet - for other users with the same AR Roles, and the same AR Data Access, data is returned.

Some of the other users might have slightly different other roles, not for the AR module, but they have the exact same 2 AR roles with the same data access, and they can see data.