Jai Auto Chennai - Pulsar DTSI 180
Silencer getting rusted

I own bajaj DTSI 180 cc pulsar. its 2 yrs old. The silencer is getting rusted. i have complained this several time to Jai auto while service and also paid 700/- for coating it. But still it is getting rusted. Also i heared that Pulsar silencer life is only for 2 years... Kindly check for the possibility to change the silencer in my bike.