Hello there,
Are you getting the same behaviour in onboard keyboard also?
As this behaviour occurs only on shift keys we can assume that this is not an hardware issue.
Have you tried plugging in another keyboard to see if the problem persists? Have you connected your keyboard to another machine to verify that the keyboard itself is faulty?
a) Press Windows key +X, select Control panel
b) Change the view by option on the top right to Large icons
c) Click on troubleshooting and click on the view all option on the left panel
d) Run the Hardware and devices troubleshooter
Hope this resolves your Query !!
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