I can print from my MacBook Pro but I can no longer print from my iPhone or iPad. My printer is Epson WorkForce Pro WP4740. The message that pops up is 'no air printer found' when I try to print from those mobile devices. Any help will be greatly appreciated. UPDATE: Also, the printer will not allow me to change ink cartridges. Usually, when I open to change a cartridge, the carrier slides toward the middle. Now it does not and just sits on the right side and gives me two short beeps.