Boggy aerox 70

Hi everyone, i have just got a 2008 aerox and i am quite new to mopeds as i have only ever dealt with mx bikes but when i got the ped started it does not idle it is very sluggish at setting of and i cant go full throttle or it would bog but when 3/4 of the throttle is held it hits the band but dies straight after and stays at around 30 mph. Any help please!!