Discovery WELLTHfund is not what it claims to be

Discovery WELLTHfund advertises that they cover a hearing test as one of their benefits - however, I had my hearing tested with a very established and well-known institution and Discovery refused to refund me on the basis that the two practice numbers were "wrong"? I find this very convenient for Discovery to decline a claim....why bother to advertise a benefit if you're going to select arbitrary excuses to refund the expense? I am now paranoid about using any further services as I am convinced I am going to have the same problem going forward.