First, are you able to clear 1/2 with ease. Use a bouquet, are you able to clear the lighting, fire and ice mod within the 3 turns(including move)? If so, then you shouldnt have problem with the 2/2.
I didn't bring the heart chocolate, i bring the blind potion. Activate beserk skill before entering 2/2 with bouquet and atk root.
Once you are in 2/2, blind the wings (1 or 2, depend on you) and faye protection. The DD with the mod should be able to clear the mod in 3 turns, similiar, just keep refreshing the bouquet when its up. (you got 3 more, and equal to 6 turns) The one with the boss (should be the bersek) also need to keep up with root.
When either wing skill is up, just stun(before that, just blind). Then when DD mob is done, walk over.(Thats why dragoon is good, because they can just fly over)
During the 5th turn, (when the first stun potion wear off), if you still cannot down the wing, then something is not right, your damage is not high enough.
If the above happen, you need to pull a 10k plus berserk ally to help. Dont waste time trying to clear using your own heroes, you just wasting your energy and potion.
For me, I just pull a super strong ally. If you got berserk, find a 10k drake. if you want 2 drake, which i dont advise, because u need beserk spread atk to clear the wings, then you pray hard the skill trigger keep popping.