This is Australian Debt Recoveries Services, sometimes an automated call other times, a person on the other end that wont listen properly, they are chasing their Bounty for unpaid debts.

This number belongs to debt collectors chasing unpaid accounts

keep calling for someone I've never heard of... won't agree to stop calling despite numerous request

They are debt collectors! Maybe you owe someone money?

These people ring me all the time & no one on the other end