car cannot be fixed because an incorrect amount has been paid

Hi we have logged a claim with outsurance claim number *** and sent all the required docs and pics. the quote from the panel beaters came to 12 000 and outsurance decided to pay 8 000 with no explanation why the payment is not the same as the quoted invoice (less the access). this is **************** and no one is interested in assisting the poor pensioner that has been loyal to these ******* for years

please can someone help

thanks