Keeps calling but hangs up when call is answered, cannot call it back??? who/what is this?

I have also been recieving these calls since i enetred a comp..not MKR but another comp...very annoying!

I just received a call from the same number. I haven't got a quote or entered MKR comp so not sure who it is. Other random numbers I get calls from always trace back to my phone provider (Optus).

All I do now is block the number.

Yet another number that's calling and hangs up straight away. I would like to know if people who have been getting similar calls from these numbers also got a quote for health insurance or entered the comp for the car through the mkr website? They're the only different things I've done before the calls started.