Claim rejection

12 February 2024 I took out a policy with this company. On 8 April I had a warning on the car dashboard that the car will overheat if driven any further. So I towed it to a place where I normally service it, Vagcore Automotive. A diagnostic test was run and the results came back that the coolant sensor had malfunctioned therefore causing water from the coolant system to go in the engine harness thereby causing a corrosion in the electric wires. They refused to cover this claim on the primise that they don't cover water damage. When I argue that the root cause is not water but a mechanical failure which I'm covered for they refused to listen. After this, because the car has comprehensive insurance with Momentum but is out of manufacture warranty, I made another claim to Momentum. Several days later after their assessors inspected the car they also refused the claim saying the root cause is not water but the failure of the coolant sensor. Therefore making it fall under mechanical failure which they do not cover.