Is your fax showing as "on hold"? Here is how to send this out:
You will be brought back to the document to where you can make any edits in the document and edit or enter the recipient's fax number to send the fax.
If you are sending a fax from a free account and your fax is on hold, try updating your billing information as sometimes the fax is on hold due to the payment. You can learn more about pay as you go here.