I'm losing my mind

Hey guys,

So I have a little boy who just turned 7. Hes fantastic. Smart, sweet, funny and all that. The only problem is listening. He will go weeks and sometimes even months being ok but certain times and with certain things he will just flat out never learn.

We have tried:

Timeouts

Grounding

Taking all games/toys away

Star board to encourage good behavior

...it always comes back to the same thing. He thinks he can tell us no. He ignores us. He throws MASSIVE fits over essentially nothing.

...help?