Epic Cards Battle

when i complete the 3rd objective ,the game still shows that i have not complete it.
I have try 4 times and still i dont complete it.
i use 6 nature cards like the objective said and i have complete objective 2 in previus battle.
Do i need to complete together objective 2+3 in 1 battle in order to obtain it?

Yes in order to achieve 3 stars you must complete them all in one battle.

thanks