Exhaust fans- have said no to these people so many times and still they ring!! Yet another number blocked

I have received 3 calls in the last two days; all the numbers have the Melbourne (03) area code and the number starts with 9125 - only the last 4 digits are different. I have picked up some of the calls, but not saying anything; after a few seconds the caller ends the call with nothing being said.

Caller: I dont know

I've had heaps of calls from numbers starting with 03 9125, with the last one ending 8049

Caller: I don’t know

Stop calling! To do with Vic govt funding of replacing ceiling exhaust fans, trouble is I have not lived in Victoria for over 6 years.