Bad service from Renault sa

I bought my Renault in roodepoort Renault in 2019 and in late 2020 the i had a problem with gearlink, i took the car to the dealership and they told me that the battery was leaking acid and that acid dropped on top of the gearlink cable and damaged it, but to my surprise they said i must pay for the damaged cable as it was not covered by the manufacturer warranty, remember that i was told that the car is covered by 5years manufacturer warranty.