Failed to receive all of my money back from cancelled flight
 

Hello,
I booked a flight on Qatar that had multiple change overs to go to Indonesia. Qatar made changes that would make it difficult to get to sequential flights. They gave me the option to cancel. I was flying with an associate of mine. We both cancelled. She received full reimbursement, and I received partial. They still owe me $635.00. For the past 3 weeks I have emailed them with no response. They acknowledge receiving the emails, but no follow up. When I call, they say they can't do anything.
Thank you