Repudiated CLaim with no valid explanation

My Vehicle's timing chain gave in pre maturely after coming from a Major Service. The Timing chain stretched which is a mechanical failure following a major service of replacing engine oil. . As part of my AA vehicle warranty , my timing chain is covered and its components. Nothing in the policy states what specifically of the timing chain is not covered such as stretching. AA told me if the chain snapped they would have paid the claim, The vehicle came out of a service and two later the engine light came on, resulting the engine to misfire , if i drove the vehicle the engine would have ceased and caused major damage... Your policy state the driver should take precautionary care , which is what i done , when i stopped driving the vehicle any further to prevent any further damage, but that too one is punished for, so you would pay for damages resulting in overR30000 but won't authorize mechanical failure for R120000. The repudiated claims reasoning makes no sense. I registered a complaint and no one from AA contacted me for two weeks.