I haven’t done "hard enduro" with my Husqvarna TE250i 2022 model motorcycle, only medium-difficult terrain riding. Recently, I’ve been having issues with stalling at idle and choking when giving throttle. When I took it to the service, they said dust got into the piston and damaged both the piston and cylinder, and they need to be replaced, which is expensive. I’ve always used "Motorex" oil and never neglected maintenance. I cleaned the air filter with cleaning solution and lubricated it with Motorex air filter oil. What’s the actual condition of the piston and cylinder, and what could have caused this?