Pay my money back!!

My son and I visited the dermatologist together on the same day. This Dr charges Discovery rayes but you have to pay direct and then claim. I submitted two invoices: one for me and one for my son. This was done on the 7th September. Yesterday, 11 September, I was told that only one claim will be paid and not the other???? This is ridiculous! I've escalated it with the call centre staff. No one can help. No managers or supervisors around. There is not even a direct contact email or phone number to use if you have a complaint! I even logged it on the Facebook page and still nothing! I want my money back! This is *******! How can one claim be paid and not the other! Same doctor! This is ridiculous! Discovery is happy to deduct premiums on time every month. No issues. But when it comes time to pay up, the customer is out of pocket and has to fight for their money? So many phone calls and so much air time wasted too! Not right!!!!