This number called and after checking it seems it comes from Bangladesh. Telstra states it is not their number. The caller stated that my land line and internet will be cancelled because I hadn't paid the NBN.
Well that is strange because NBN is not in my area yet and I wouldn't get a call threatening me.

Caller: Pretended to be from NBN

Rang 4 times over 2 days

Caller: Nicole

Told Press 1 or your NBN will be disconnected - we haven't NBN in Bayview yet.

Caller: (08) 8388 9543

says internet & phone will be cancelled or changed...I think, as the accent is barely understandable. When I said please explain she hung up. Checked NBN roll out, no NBN in our area yet

Got two calls 12 hours apart saying that my internet would be cancelled in 24h because I and not made the change to nbn. I have just moved to a new property and I have nbn. Scam it seems.

Caller: Pretended to be from nbn

Auto dialler that left message on my voicemail saying that it was nbn calling to say my phone line and internet would be disconnected in 24 hours unless I pressed 1 to make contact with the 'technician'.
Obviously a scam call similar to fake Telstra calls.

I tried to ring back the number (08) 8388 9543 but reached a silent voice mail