Hot Mama's Fitness Robin Smith, Owner Company did not fulfill my service and has not refunded my money Weatherford, Texas

I signed up for personal fitness with Robin Smith the owner of Hot Mama's Fitness.  I attended 4 sessions and Robin added 2 more women to my training time which was a personal session, she also had no idea how to handle a knee injury that I had informed her about days prior, when I showed up for training, she wanted me to do squats and lunges.  Because of my complaints with the knee injury and the fact that I was to have personal training not a group training, she told me to find another trainer.  That is fine, but she has not issued a refund for my unused sessions.