Still Cannot Win Galactic War, Can someone help me?

So I am level 70 and still have not won galactic war, sad right? My team right now is 4* Vader( level 66 Gear 7), 4* Maul (Level 70 Gear 7), 7* Sidious (Level 63 Gear 7) , 7* Luminara (Level 64 Gear 7...