Hello Badel,
I searched our knowledge base and found this article on AirPrint. If you are still having issues after trying these steps, I suggest that you call into our support department for assistance @ 1-800-835-6100.
I cannot find Xerox B305 printer nor on my iPhone XS Max neither on MacBook Air via AirPrint. Original drivers on macOS are installed and all devices are on the same wi-fi network (printer is disconnected from Ethernet).