You dont answer to them you answer to your supplier.
Ask them for their name and proof of identity, there are thousands of scammers out there just waiting to unload your pockets.

Bunch of gronk debt collectors

(03) 4116 2003 - very annoying and unprofessional.

I called back number (03) 4116 2003 reached IVR for the Dun & Bradstreet.

dont answer

scam debt collectors

They claim "It's a glitch with new system". I've experienced the 'glitch' 3 times in last week. Called them told them how unprofessional it was and I was blocking their number. And all over a false/dodgy invoice claim too.

I called back number (03) 4116 2003 reached IVR for dun & bradstreet debt collectors.

this is Dunn and Bradstreet they ring and when you answer they hang up getting you to call back then hassle you to pay straight away