Where did I go wrong?
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you should play 25.Rxb3 then he cannot take with pawn since 26.Rxa8+ Kh7 then it is true he can promote to queen but u take it with bishop or simply exchange with knight and you are front because you had rook.then he possibly takes with queen.after 25...Qxb2 you play Nb3 and protect your rook and you also stop the black's pawn on a-file from promoting.Then it is nearly equal position.