Losing the link to the scanner

I am a new user and trying to determine if PDF Architect is right for me. So far the experience has been good but a couple of times the connection to the scanner (which is part of a Canon MG4250 printer) has been lost during scanning. Switching off the printer or closing PDF Architect has no effect, the application just displaying ‘please wait…’ when I try to use the scanner again. This seems to be incorrect as both printing and connection to the native Microsoft scan application is successful, and so there must still be a link to the device. If I reboot and start PDF Architect again, selecting the scanner shows the input settings as it should.
I am connected to the scanner wirelessly and am using W10. Can anybody tell me why this happens and what to do to fix the problem?