I have an iphone5 and recently have started to receive unwanted calls. One particular number plays "on hold" type music if you call it, and another plays a message saying "you have reached a non working number." I get these calls every day. Anyone else?
I remember putting my number on the no calls list though.
There's nothing you can do. You can't block numbers and calling your provider will do nothing since the only thing they'll be able to do for you is change your phone number (for a fee).
Every so often I receive the absolute freakiest prank calls to my number (it's been going on for years) and there's nothing I can do about it.
It's actually a little easier. There's no need to create any contacts. Just tap "Phone" and "Recents" and find the offending phone numbers. Tap the "i" enclosed in a circle on the far right and choose "Block this Caller" on the bottom of the page that appears. That's it!
When I was a kid I'd make really weird prank calls. I'd pick up the phone, dial a number, put on a gruff voice and say "This is Satan." when I had ennui I'd add a French accent say "Zee ees zee fronsh Say-tun."