What's the point of charging scheme rates?

I work for a Dr's practice and working with GEMS accounts is an absolute nightmare! Members request medical aid tariffs to be charged as they can not afford co-payments/outstanding amounts and then expect that the accounts get settled! Nope, not GEMS! they leave the member with an outstanding amount of an average of R50.00 - R60.00 with a note on their statement \balance payable by member". I don't have the time to call and query each account with an outstanding balance and then get irate members calling me asking why we overcharged them? And when I do get the chance to query an account"