I'm fairly certain that was an issue in early builds of the firmware, so just update to the latest from this link, call your cell from the home/office phone that the fax is on, and send an email.
If it works on this one, apply it to your other 5 units so they all keep the same firmware levels for convenience
Our WS3220 has had this 'issue' for quite some time, and frankly, my wife is about to put a 45 caliber hole in this printer if I don't come up with a fix for this...
EVERY time someone is using the telephone line that is also connected to this AIO printer/fax/scanner, the printer cannot be used to scan or print anything... Apparently, if it detects that the phone line is 'off-hook', it seems to then 'presume' someone is trying to fax something and then 'defaults' to only allowing a fax... So no one can scan to a network connected PC nor can anyone print to it. Surely, this is something to do with some type of configuration issue somewhere..? And if so, then WHERE is this to be changed..?
I've tried hiding my guns, but at some point she's gonna kill this printer... HELP!!