Bonitas premium and income verification unhappiness

Hi. I am very dissatisfied with the medical aids admin management for my mother membership number ********** 2711 whereby her premium was increased over 50% because a form was not filled in due to the consultant not sending the form for her to fill in on income verification by December 2017. She is 71 years old and only gets a government pension so medical aid premium hike of R3901 is a lot to pay and the sad part is all communication to the consultant on income verification stated all the documents were in order. The service from the medical aid is brilliant, the admin of the premiums etc is not. I feel better communication could have prevented this and right now is creating so much stress to fork up the additional money.