Why can't I get water out of my washing machine taps?
If there are shut offs further up stream you can turn them off and then remove the sharkbite elbows nearest the washing machine valves. You can then have someone briefly turn on the valves that you shut off to check if water is flowing. This will tell you if it is the washing machine valves or not.

The sharkbites can be removed by pushing the orange part into the fitting while pulling the fitting of the pipe, this can be tricky. there is a special tool for this but you can do it with crescent wrench if you size it just right . 
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