I keep getting them too.
I tell them to stop calling but they don't.
How can I stop this?

I complained to the Don Not Call Register, as my No. is registered with them and they are looking into it. Over the past 3 days/evenings, I have received the call and today someone spoke, I couldn't understand her, but asked her to remove my Number from their list. Her reply was, you shouldn't give your Number out. I told her not to be a smart arse and hung up.

they call everyday its annoying

Got very broken call from number, called back and got hold music for over a minute

It's so annoying I got calls from (03) 8807 0901, 03 & 05.
How do I block them?

Silence on the other end

Spam indeed

spam