regional suspicious

dodgy.

Caller: Debt collectors

Best thing to do is to simply ignore the call, let it ring out, and make sure you don't have any ID information on your message bank like "Hello, this is Muhammad Al Iraqi". This is to avoid them saying they have contacted you personally, thus resetting their 'contact clock' (debts are unenforceable after 5-7 years, as long as you haven't 'interacted' - be careful!).

Don't block their numbers either: they could potentially say this is evidence you acknowledge them (remote chance, they have no access to call records or your phone).
If you can, tell your family/associates to NEVER confirm/deny anything about you from a random call, just hang up. If you have easily searchable stuff about your job or social media and work/family contacts and links, more fool you: they'll come after them too.

Caller: Debt collectors

Debt collectors

Add a cross for my 5th mongrel idiot for the day

Caller: Unknown - I let the phone ring out

Obvious scam call which I let ring because the number is an 03 Melbourne number and I dont know anyone worth talking to in Melbourne anymore.

Scam

the number is regional suspicious

I called back number (02) 4302 4834 rang once then gets disconnected automatically.