Am I doing something wrong with Gog-Mazios?

I am sword and shield user who cannot beat Gog-mazios (not including the story) and am wondering if Im doing something wrong because I am close to quitting.

I use fire for first and second phase and can clear them with no issues and no faints. I use all support hunters available to me.

I repeatedly triple cart on the third phase. I use dragon element, I use charged up wyvern lasers, I drop the boulders and I either fail the dps check or get stun locked during the animation by a boulder and die to damage from the ambient fire radius.

the fact this fight locks the end game progression is really getting to me and I'm starting to consider just giving up on the game.