Unreliable - Promised written refund not paid

I had a confirmed reservation for the flight JQ 62 on Sept. 15th 2012 and a prepaid seat fee of SIN$ 120 for specially requested seats with extra leg room (I am 2 Meter tall). These seats were also confirmed.
Arriving at the check in they told me that the confirmed seats were taken are we were given "normal" seats, a horrible situation for me with my long legs!
Unreliable I: Although you have a written and paid confirmation you don´t get your confirmed seat!
After returning from my holiday I wrote Jetstar on Okt. 2nd and claimed back the SIN $ 120. On Okt. 16th Jetstar confirmed again by email to refund the amount within 15 days. Until today - Jan 9th 2013 - I did not receive any refund. I wrote Jetstar 3 times again and did not even get an answer.
Unreliable II: Although you get a written confirmation for a refund you don´t get any money back!
I will write now to the CEO of Jetstar and Quantas and will complain again about this unbelievable behaviour. This is not the way a company should treat their customers.
I am realy upset about the ignorant behaviour and as I am a journalist in Germany I will follow up.