I called back number (02) 8651 5372 spoke to a woman but did not say for what comapny.

Caller: Suzanna

A lady named Suzanna called asking about my Sister in law. And if I could pass on a phone number for her to call her back. She also said she had sent an email and mail to her (Which my SIL never got) . I asked her what it was in relation too and got back that she wasn't not disclosing that as its 'private and confidential', and she got my number from my surname as it matched my SIL's maiden name.
Weird if I do say so myself. Googled the number and got this forum and also alot of Federal government stuff too.

Caller: Suzanna

Suzanna called me saying she was trying to reach a family member, i asked a few times, WHERE she was from and was saying she based in Sydney, i asked WHAT company and she wasn't not disclosing that as its 'private and confidential', not sure how she got my details as this person never puts my details done. I asked if she is from the ATO or sper, she mentioned not directly from the ATO but kinda? not sure what that means..... seems and sounds very sus..she also calls from NO CALLER ID

Caller: Suzanne Akkari

Definately a debt collector. Has been ringing family asking for private information and not stating who she is or who she works for.

Caller: Suzanna

I called back following a message left on business answering machine. Dodgy debt collector I'm guessing. Would not identify herself, was looking for someone that used to work for us and wanted me to provide private information re forwarding address etc. Not happening.