It seems Jedis can use the force to lift really, really heavy objects (like entire spaceships for example). But when it comes to lifting their own bodies, they can only use the force to jump higher/farther but not defy gravity entirely. Which is awesome no doubt, but what makes it harder to lift your own body as a Jedi than an (I'm assuming at least 200 ton) spaceship?
Jedi do fly.
In a scene of Star Wars Episode 2: Attack of the Clones movie, I remember Yoda flying while sitting in a basket. It was not jumping, it was a pure flight which was a kind of Force Levitation (but it may require lots of concentration, that's why it's not common). But, it's possible that it wasn't Force Levitation providing Star Wars universe has repulsor tech (I'll dig more to identify whether it was Force Levitation).
In Legends canon, there are lots of Jedi capable of flight (Some even do it on everyday basis like Superman). Luke Skywalker also does fly in the Legends canon.