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You can try following one by one :- 1. Select the printer's "on line" mode, or deselect its standby mode,2 cycle the power, or reboot your MacBook3 delete the print job4 reset your printing system and reinstall the printer.
locate your printer icon— right click on printer icon— find and make sure to click on the following: Use Printer Online
If you do not see this option then skip to next instruction.
Also try rebooting your printer,Iphone and router.
you are trying to connect to Printer using Bluetooth or Wifi ?
Please try this as well :- go to the print/fax window and highlight the printer and press the"-" button and remove the printer from that section. Then press the "+" button to reload the printer back on.