You may witness an offline error message while working with HP printer through Mac. This is called communication error; however, it can be solved easily with these methods given below:
• Try to reset the printer by turning it off and unplug it then again turn it on and plugin.
• You should go to Mac and search for other printer connected to the system. Now you need to delete all other printers connected to the Mac than try to connect the HP printer again.
• Go the list of printer and with a right click on the blank area, choose reset the printing system, and then try to print from the HP printer again.
• You can also try to the current print queue and add your HP printer again to the Mac and try to print again.
These methods will surely be solving your issue easily but also have the option to choose hp support assistant number for further assistance and guided solution.
Read more: hp printer assistant support