I called back number 0402 962 241 rang 2 times then goes to busy tone.

I have been constantly contacted by a power company. I used to answer and tell them to take me off their list (to no avail) but now I simply block every number. They just keep finding a new telephone to ring me on. While I can't be sure that this is just one more, these numbers never leave a Voicemail message. Serial pest!!!!

you can't call them back, block em. It actually says this user is not accepting incoming calls.