Why pressing sleep/wake + home no longer take a screenshot on my iPhone 5s?

[iMore Question]

I used to be able to take a screen shot when I pressed the sleep/wake button plus the home button on my iPhone 5s, but for some reason it's not working now. Is there some setting that I accidentally changed?

 

[kch50428]

When was the last time you rebooted the phone? Try that...