If you have problems receiving a fax, make sure paper is loaded, the phone cable is connected correctly, and the phone line works. To automatically receive faxes, make sure the light next to Auto Answer/Space button is turned on. See Automatically Receive a Fax for details.
Make sure that your recipient’s fax machine is turned on and working.
If you’re using DRD (Distinctive Ring), try setting DRD to OFF or ALL. If the fax answers when turning off DRD, the issue is with the ring pattern and you should contact your phone company.