Toggling between windows in server

I use a windows 10 laptop for work and connect to a server Citrix.

I have a second monitor and have the screen extended so that I view the server on this and when I have selected an item in the server I can toggle between windows within the server window using alt + tab.

My electricity went out for a second earlier and when the router reset and I reconnected to the internet when I selected a window within the server and tried to toggle between windows within the server window it instead toggled between windows on my laptop (one of which is the server window). I really need to be able to toggle between windows within the server using alt + tab as it is a huge waste of time using the mouse to select the other file/folder each time.

Any idea what happened and how to fix it? Thanks.

smuggler.ie

Sound like session issue - have you tried log out/log in server, perhaps even restart laptop in between