It sounds like a dirty carb.
Using a fuel system cleaner may help.
SeaFoam is good, just add the correct amount.
If you can ride the scooter, about 3 tanks-ful the performance should improve .
Also, I add Sta-Bil to my gas every time I fill up,
so if I don't ride for a shile, I don't have to
worry about the fuel going bad.
Scoot Safely,