Numbers starting 9969 calling at all times of day. No message left, block numbers but new number calls again and again

Multiple calls received from numbers starting 03 9969 never leave a message.

No voice message left, when called back asked to hold line for an agent and apparently drops the call.

about a dozen calls so far for last week all start 03 9969 81xx SPAM different variation of these numbers each. Ignore Then Block

Caller: Health Connect

They started to talk to my Answering machine, asking to clarify some details then hang up. Health Connect - Survey.
Also used (03) 9969 8116 & (03) 9969 8124

All numbers starting 9969 just don't give up. All times of day & very persistent. I block them all & another one pops up. How do we stop them?

I am so over these pests - I don’t answer calls unless on my contact list and they can’t be bothered to leave a message so they are spam / scam calls. Now another blocked number 🤬🤬