wireless signal of printer not working. devices detect no airprinter

-wireless signal of printer not detected by ipad and computer

-message on devices when try to print says cannot find any airprinters

-we have already tried re-installing apps/software for the printer on ipad and computer and still does not work so is not an issue of updating

-it was working properly in the past

-we have tried turning the printer off and then on again which doesn't help

how do fix this problem. the printer is a Canon printer MX495