Originally Posted by
javabytes
This. It is very likely there are no miles to refund. Once an award ticket is partially used, it will not be refunded.
Sounds like the OP just paid $150 to refund zero miles. The ignorance of some agents can really hurt someone not expert in Skymiles program rules.
If I were the OP, I would call back to see if another agent will reverse the ticket change charge because it should have been obvious to the first agent that there was nothing to refund.
What the OP could have done was to pay $150 to change the return to any future date with low availability in hopes that he could use it later.