Used Yamaha Waverunner Yamaha Waverunner Starting Problem?

Yamaha Waverunner starting problem? - used yamaha waverunner

I have a 1996 Yamaha Waveventure and appeared normal. It was not used for about four months, but the battery in good condition. It has a starter button and, as a rule all the way when pulling the throttle body. Does anyone know the problem, or perhaps suggestions on how to implement?