Why are touchscreen touches on the monitor displayed on the extended screen?

Question

Windows Server

Subject, there is a cash register, it works on Windows 7 (or rather, there are 7 such devices, but the rest work on POS 2009). This machine has a problem:
there are 2 monitors, one for the cashier, the second on the buyer's side - the buyer sees the videos.
the cashier presses the display (working touchscreen) - the monitor is in extended monitor mode - for some reason the touches are displayed on the second display (on the buyer's side - for this, he turned on the icon with a special one so that you can see where the touch occurs). if instead of an extended monitor you choose - duplication or just display a picture on one monitor - then there are no problems

Answer 1

wheelbarrow calibration is needed