Caller: Scammers

I had a missed call today on my mobile. The number displayed on my caller ID was (02) 6431 9654. I dialled the number and there was an announcement, which said: " the number you have dialed is not in service".
Ive been receiving many such calls from numbers which are "not in service". These are the types of calls telephone scammers do from their fake phone numbers. They just keep on calling, it could be in the mornings afternoons or evenings. Some times tgey ring once or even twice just so you miss their call. It's designed so you answer it or call back. Don't answer it. Don't talk to them. Hang up