ZTE base unit keeps losing connection

Hi there, we’ve got the ZTE WF721 unit for our home phone and it has suddenly developed an annoying habit of losing connection.  Pick up the phone and no dial tone, box has full signal, looks fine.  Turn box off and back on and that fixes it.  Is my unit suddenly defective?  Should I just take it to a Koodo kiosk somewhere and ask for a replacement?  It’s well over a year since we’ve signed up.