Social media at post of says parcel sent to Australia but it's destined for the United Kingdom.

Hi there. I posted a parcel from Garden View post office headed to UK on 26 September. It's tracking number CN ********** 63ZA. Iv been tracking it only to find last noted was 9 October. I then emailed ********** Her response was that it was sent to Australia ?Iv also emailed her a few times but no response as it's destination is the United Kingdom. The lady called Debbie asked me if I never sent it there. That's a definite No!!! My question via several emails to her was what happens now. How do I get it back on track to its original destination as it's clearly the fault of the post office. The sad thing is iv not got any response email as to what would be happening next.