BMW Not fixing Fault with Motor Plan

3 Months ago - my vehicle didn't start - I Called BMW On Call - they came over - checked the vehicle and then decided to tow the vehicle away as he could not repair it on site. BMW On Call gave me a courtesy vehicle for 5 days. They took my vehicle to Bruma BMW for repairs. They repaired the vehicle : Upon me collecting the vehicle BRUMA BMW told me the problem was that rain water ran down the edges of my panoramic roof and dripped into electronic box in the boot which corroded the wiring, etc. they fixed the problem.<br> 3 months later - 13 September driving from Durban to Johannesburg with my family - I stopped off at the BP Oasis garage after the Marian hill Toll Plaza. the vehicle again didn't start -this time BMW on call came over check ed the car and then towed it off to Pinetown BMW in Durban - NOW BMW HAS REJECTED THE REPAIRS AS THEY NOW SAYING THAT THE BACK WINDSCREEN WIPER WATER CABLE IS CUT AND THAT WAS DRIPPING ONTO THE ELECTRONIC BOX AND DAMAGED IT. THEY SAYING BECAUSE IT IS CUT - THIS IS NOT COVERED UNDER MOTOR PLAN AND WILL NOT REPAIR IT. <br> <br> THIS IS A TOTAL DIFFERENT STORY AS TO WHAT THEY TOLD ME 3 MONTHS AGO.SOMEBODY PLEASE HELP - LEGALLY