Called work

Who are these people and why do they keep calling?  No message, nada.

Get calls from this number at least 3 times a day. Never anyone one the other end of the phone. Getting very frustrating!

i deleted my fax header info, date, and time of day.  let it ring through to my fax machine, and they haven't tried to call for 2 weeks now. also beware of emails with 6118 in the address. probably the same people.