help we need assistance.

well my Dad had an policy for his gran child she was alone in her policy and pays R55 per month covering her for R10 000 upon claim we now told that because she is under 6 years they 25%which we were not told when taking up the policy and we are old people we went aware of this claws they feel like we have been taken for a ride while still moaning our grandchild. please urgent assistance in this matter. we trusted old mutual now we unsure about their services.