I tried to call back the number (03) 9544 5287 but the person who picked up the phone disconnected the call

Caller: Don’t know

Says from Clayton. Victoria. They hang up when I answer. Now blocked

They said they were a Telstra business partner? I didn't take the call though, was dubious why they would call me.

Rang for 5 seconds, and then disconnected. No voicemail

Caller: Unknown number another spam

I been getting a lot of spam numbers nearly everyday I don't bothered with such callers I block them straight away

Left no message, scam call.

Definitely spam. Don’t answer. Dodgy

Offering free water system upgrade funded by govt
I asked to be taken off their call list, and they said they could not.
I asked to speak with their manager and they said No.

Usual odd looking number... no message left. If it's Telstra "business" shame on them, how hard is it to leave a voice mail... eh ? Blocked.

They called to offer me free solar water if i was eligible.

there must be a way to black list this number, a nuisance

Didn't leave a msg. Dodgy call. Now blocked.

Missed call no message left. Blocked number

I called (03) 9544 5287 talked to gentle person in regards to my Telstra account, helped me to change my home internet plan to new casual plan, and updated my existing mobile contract too, good service :)

I rang back the number (03) 9544 5287, spoke with someone who hung up right away