Can't connect with XAV5001 Powerline AV 500 Adapter

This has worked for years but all the sudden it does not--I can not find printer or print. Sometimes this happens and I have to un-plug unit from wall to have it work. Tried that but it still won't work. Pressed all the buttons, moved furniture to get to the other unit. Attempted to sync security encryption key with powerline utility for both and still can't print. 

XAV5001 Powerline AV 500 Adaptor plugged into the outlet and hooked to Xfinity modem via ethernet cable

Macbook pro that uses wireless to hook to Richo C320 printer

Printer uses ethernet cable to hook to XAV5001 Powerline AV 500 Adapter that goes into the wall.

Used Netgear powerline Utility 3.1.0.4 on a PC and have done a factory reset and also selected a new security encryption key (keeping ti HomePlugAV) I can see both units are connecting when I refresh. BUT still can't get printer to respond.

HELP--many thanks!