IT will provide dial tone and calling permission for your fax machine. But there are many different models on campus. Your office staff needs to be familiar with the manual for your fax machine and do some troubleshooting. Remember your fax machine is physically connected to a specific wall jack. It wont work on any jack. You cannot move it without assistance from the IT department.
Did this fax machine work fine and just started acting up recently? What changed? Was it moved?
Is the problem with sending or recieving? For recieving, call the four digit number of your fax machine and see if it answers and if you hear the fax tone.
Does your fax machine have an auto answer button? If it does, its easy for it to become unselected and then it wont pick up faxes. That can also change with the settings in your machine's configuration. Read the manual to learn about the available settings.
For sending, do you usually dial 9+ the phone number? If your trouble is with dialing only 4 digits, try 9 + the full 7 digits phone number. If your trouble is with faxing long distance, contact the help desk to find out if you have long distance permissions set.
Is your fax machine covered under a warranty?