Yamaha Scooter turns off when upon idle. What is wrong with it?

i think it might be in the ideal control. look for the cable the gose to the trotle on the motor and you will see a sping and a bolt on the end you can tightin the bold with will make the spring go wider there fore the ideal will go up. that migh be the issiue because when they clean the carb they might not have put the on how it was adjusted before. it only takes about 5 mins to do your self. if u need more help just i.m me. good luck hope this helped.