No dial tone on any of our land line phones. Only get dial tone connecting phone directly to modem.

We are not getting any dial tone on any of our land line phones or our fax machine (HP Officejet).  I tried resetting the Arris TM722 voice modem thru the troubleshooter, but that did not help.  I connected a corded phone directly to the modem where the outside line plugs in and I did get a dial tone on that phone.  Please advise.