Royal Enfield — missing experienced with standard 350 abs

Even after replacing purge valve as i have wrote in my first complaint, the engine is not functioning smoothly. This time missing started after just 10 kms of ride. It continued till the end of my journey. I rode 20 kms with the missing problem persisting before the engine turned off when fuel level came to reserve position. But the next morning (Today) to my surprise there was not a sign of that engine missing problem that troubled me yesterday. Service technicians at marikkar service centre, thiruvananthapuram are performing bad.