Call centre ringing about my non existent Bitcoin account.

Do not answer or call back. Block the number

Caller: some bitcoin trading

Somehow got my number, rang me 4 times a day for wealth/bitcoin trading. I must have got 40 of their other numbers reported as spam too. (some calls says originated from Auckland, London, and then rest were local Australian numbers. I can block them from contact as well so only my known numbers are accepted. They get charged money to ring me and I got pissed off with them, So I thought I'd cost them more money.
After my many attempts of ringing the local numbers they used, I eventually had someone answer on this number - (03) 8399 9115. So now I ring that local number and hopefully they get charged an international call rate to their home country - Mostly subcontinent Indian, and the odd occasion of what sounded Russian woman.
Spoke to them and asked to desist from calling. I ring this number and leave it on for a few hours, hoping that they are being charged. If not it lets out my anger and frustration with them. Scam scam scam.

Caller: Trading agency

This number keep calling me and they said i did register for trading. Also really rude conversation

must be a scam caller, talked about a bitcoin trading site, i've never registered my details on. They wouldn't tell me where they got my details from either. Have blocked the number, would do the same!

I returned a call from (03) 8399 9115 but the voicemail didn't mention the company name