@richbedforduk Now that I see that you are using Windows 10 I can tell you that I had something similar some time ago with Suuntolink, When I connected the watch to the computer , it wasn’t detected by Suuntolink, and no moves where sent to Movescount. Eventually the problem was because an update of Windows 10 and later Suunto issued an update to fix the issue.
Maybe here, some Windows update has broken something in Moveslink2 connection.