Like the title says, my friend had this happen and now people are calling her non stop and the need desperate help!

If anyone has any ideas it would help greatly!

Is the phone a cell phone or home phone?

Cell, and they are getting very sexual calls.

It seems reporting the advert to Craigslist is better than posting here. We can do nothing about it.
You could also report the listing as harassment to the police, but if you don't know who the poster is that's not going to get you very far.

Can you post my number on there please, then maybe I won't have to pay for such calls in future...

OK, I know, sorry, don't give me the ban stick, I couldn't resist.

Thanks guys, I told them to talk to their mother (the person is 13)
hopefully this will be resolved.

Now I *really* feel bad for my tasteless comment, I had no idea.

Anyway I hope this will be resolved quickly, either by changing telephone, or by getting the police involved to trace the caller.

I suggested that they change the number but the problem is that they are scared to talk to their mother. But I think that this will be resolved so I don't think this needs to be discussed in depth.

Thank you all for the suggestions.

He needs to contact the police and file a complaint. This is harrasment / intimidation.

Police deal with this sort of thing all the time and they usually have a good relationship with Craigslist.

He can also contact Craigslist to report abuse and have the post removed.

There is an option on all cell phones to only accept calls from those in your contact list. This would be the bare minimum first step.

Your friend can find and report the callers through their phone numbers.