Hello there,
- Is there any change before the problem happened? Such as hardware replacement, and software installation?
- Is there any 3rd party protection/anti-virus tool?
- Please check the System event in Event Viewer to confirm if there is any related event has been logged.
While connected on the 2nd screen Right click on the taskbar on the 2nd screen and then Got Taskbar settings-> Check the Auto-hide taskbar settings. Ensure You Have Enabled Taskbar On Both The Monitor.
You should also try updating your PC and then check if you meet the case or not.
Hope this resolves your Query !!
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