aussiemate

I'm not sure if this is the right place to post my query, but since I bought my ticket at Qantas, I'm giving this a try. I bought an around the world ticket and was unable to use one of my North American segments because a British Airways flight I was on arrived after my connection had already taken off. I hired a car and drove the 2 hours to my next destination because I could not wait around for the next available flight (6 hours later). My segment was reinstated for MIA-RSW, the flight I missed.
My question is, can I get my segment reinstated to be used for a new destination. I will not be traveling to MIA again, and I would like to use the segment to go to the west coast. Any experience with this or advice on who to contact?

Thanks!!

Aussiemate