Doesn't stop calling our main home line allday long anywhere from 10-15 times daily

Received 6 calls from this number, which was a fax.  Tied up my phone line for approx 1 housr.

As i finished the last message I rec'd another!

Finished typing this note and it phoned another 10 times.  If you just hang up, it calls back immediately.

I tried entering 00000 when prompted then by 604 cell phone number after the first call but I got 3 more calls after that.  How long should it take to remove someone's number?

Calls my land line incessently. What can be done to stop these people?