Piaggio Zip 2T 2015 transmission problem

I've got a 2015 Piaggio Zip 2t
Only 3500km on the clock but had a few issues of late.Had problems starting and found out it needed a new generator which I had fitted by main dealer a its be running great for a couple months.On way to work yesterday it cut out on me after half a mile,wouldn't start so wheeled it home,this morning it started but when I pull on the throttle,the engine revs in and out but the bike won't move even if I pull the throttle all the way back,I'm a novice so any help would be appreciated...

 

Belt snapped.