Do you have your 2 screen setup by expanding the window into both monitors? Then rearranging panels to achive you results?
If so, did you save this as a workspace? If so reset the workspace.
The window was indeed expanded to both monitors and the monitors were aranged correctly but upon your sugestion I temporarely switched everything back to default "one monitor setup" and then back to "two monitor with extended window". I also did a reset of my workspace as sugested.
The result is that everything is back and working as it shood. Problem is solved.
Thank you very much.