Scam.
They say they are from VisaMastercard (they clearly dont know they are different companies)
They ask if you have made a USD$1800 in the last half hour
They ask if anyone else has access to your credit card
They say they are going to help you cancel the payment

AT this point they realised I was messing with them and hung up on me
S-C-A-M

This number called me, call ended under 4 seconds.
Likely a scam number or automated dial.

Caller: They said they were Telstra and call was showing Dubbo

I have blocked number

Scam. Dubbo number.

Caller: Scammer

Number says it’s from Dubbo. Said they worked for Visa MasterCard and they wanted to verify a transaction. When I asked what card, they said commonwealth. I said I didn’t have a card with commonwealth and they quickly hung up.

I just a call from dubo. When I answered no reply. Engaged signal
Also call from (02) 9423 3867 same engaged signal scam

Caller: Unknown

Definitely a scam. Said I had an issue with my Visa/Mastercard. I said I don't have either and they hung up

Caller: A Scammer

SCAM..! I have a different phone so I don't need to hand out my real number when I'm not sure about the source. I get spammed and scam calls all the time and I have been pranked by this number and also had the Mastercard/Visa BS peddled to me like an earlier comment mentioned. It even came up as a scam number via Android. That's because it is a scam number...

Caller: Did not identify himself

Claimed to be from CBA. Do not entertain caller.

Caller: Debt collectors

Debt collectors

Caller: They said they were from Commonwealth Bank

It was definitely a call centre and the person had an Indian accent. I hung up as I have no accounts or dealings with CBA and I blocked the number.

Recorded message purporting to be from EBay, concerning possible fraudulent purchase. Given 3 options to be diverted to forms of assistance. Scam.

They claim to be from the Fraud & Security Department ringing about a visa/Mastercard transaction, so I asked 'For which company?'. He replied 'The Commonwealth Bank'.
He claimed that in the last 20 minutes they detected an unusual transaction attempt on my account, from Mountain View USA on a Samsung phone, and this was the third attempt. Some business name of 'Silicon (something) & Travel'. Amount $865.00 But I didn't need to worry because they had blocked the transaction. He offered to put me through to the account manager at CBA to 'discuss the transactions'. I suggested I could just look at my account and ring them myself? He said I could do that if I wanted to but I wont see any transaction there, because they blocked it. "OK, so there isn't a problem then?" I asked. He got stroppy and said "whatever maam, it's your money" and hung up.

Same as others have reported, I missed the call but it stopped after about 2-3 rings. Didn't bother calling it back, I never do. Looked up the number and found the above info so I have blocked it now.

Caller: Telstra?

Said my internet wasn't working properly and wanted me to go into my mobile phone app to fix the issue?
I asked what the address to my house was and they gave me the correct address.
I hung up and then 4 different phone numbers called back. 2 from Thailand and a mobile number.
Sick of getting these scam calls. Wish it would stop!!!!!!!!!!!!!!!

2.5 ring tones, then stopped.
Noone with serious intent would actually persist for such a short duration.
This is how I recognise scams these days. Particularly automated systems that want you to answer, just to keep you on the "list".
Came here. Read comments.
Then blocked call.

Didn’t answer the phone but potentially a scam

Missed a call from the above number (Dubbo NSW) and I don't know anyone from there. By the time I took my work gloves off they had hung up and of course no voice msg left. I suspect it was one of those commissioned charity agencies.

This number called me, the line was just held open with no response.
Likely a scam number or automated dial.