Scooter not starting

I own a sym shark 150. Had a few problems with it cutting out when slowing down and reaccelerating or when stopped at lights, and having the feeling that it was idling too low in general, along with hearing popping noises every now and then.

Past by a mechanic just to query it and he said (i think) my carb needs cleaning. Eventually it just wasnt starting at all last week after not starting straight away for about a week or so (coincidently when the weather started getting rainy etc?). Took it to the garage to get the carb cleaned and he also replaced my gear/valve which had broken (the cause of it suddenly not starting). Cost 2200 altogether. Now 4 days later it wont start again. This time it almost sounds like its firing up but wont. Any ideas?? I was told that mechanics here will focus more on getting the bike working than acutally fixing all of the things that are wrong with it that may cause future issues??

Ill take it back tomorrow but just curious if anyone has any ideas here.

Cheers.

Change the spark plug. 90$nt and you’ll be sorted. Then get in the habit of giving your machine 15 seconds or so on cold starts before driving off. Plugs can be easily fouled when giving gas right away on a cold start while the choke is still on.