Day light *******

My car's gearbox is covered for R30 000.00 but they have only paid R22287.00 the balance must then be paid by me personally. They never gave me any reason to authorise this smaller amount. The Booster warranty cannot be reached ,having been trying for so many times to call them, first for courtesy car which they turned me down but having been stipulated in their policy document and now I need the Booster to pay the outstanding balance. I am frustrated my car is stuck at Gearbox centre because I do not have the balance of R10969.45.