Claim shortfall from Medscheme

hi, i had an operation on the 5th June 2020, i had received a qoute from my doctor and submitted to them. they qouted me based on it and i was supposed to receive back 15k but only received 8k and they said the number of theeth qoued are different to the invoice which is not true. i then showed them where they shoul look and they have refused. the original qoue from the qoctor is the same as what i submitted to claim for. please help me to get my money. my cell is *** and my membership number is *** and its the Nedgroup option. i