Analyze the game.

This was a really complex game and I do not know the reason behind them: lichess.org/mBQ7QyG3/black#0
I was in a winning position but after few moves the opponent started winning.

35. H4 is your big blunder, white happy now, because white can move
Rb6 to win c6 pawn. your f6 and a5 pawn is weak now:l Yeah opening
your opponent is losing 2 pawns.