Start by charging-up the battery.
I suggest you do a camera reset next.
It is possible that you have inadvertently set something that is causing the problem.
Go to page 68 of the User Manual and do a "Reset-All".
This will reset the camera to factory settings.
Make sure the camera is in Auto Mode and try again.
If those don't work, there is not much you can do to fix the problem.
Time to call Canon Service for help.
If they determine the camera needs service, see if you can get an estimate of repair.
..
My canon G9 shutter/zoom button has suddenly stopped functioning. When depressing the button it appears to work but will not actually take a photo. Also the zoom function has stopped working. The zoom lever is part of the shutter button. Anyone have a clue how to fix this

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