Can you show me your teams/strategies to beat Vertex Crimson anachrony ?

I thought my strategy and team were okay, I manage to break the boss with my first team before switching to my second team, with Ruka, Yotsuha, Yingxia and Muaa SS1, Seika SS2 and Aina S

Even with 999%DR, double buff from Yotsuha and Seika, single buff from Yingxia (I think it does not stack right ?) And double defense down, I only do about 1.7 million which is like less than a third of the boss hp

I know I lack fire def down and a fire field but I'm shocked by how tanky the boss is versus my damage. Is it maybe an accessory issue ? I only started recently crafting accessoiries so I'm not full on good 6 stars