Perforce source control - Workspace not showing in UE4

A person in my game project team has issues with source control.
They can sync with Perforce and get the assets on the server to their local workspace mapping (so they have it locally and everything works).
But once inside UE4 and they want to connect to source control the workspace itself cannot be found.
The server name and user name are both correct. But when you select the drop down (Avaliable Workspaces) at the bottom it thinks for a bit and then it says that no workspaces can be found. If you try to enter the Workspace name manually it still won’t work and you get the same ‘no workspaces found’ message.

Any idea what could be wrong?
Thanks in advance!