input doesn't work on if statement [duplicate]

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Why does the code doesn't work if I input "H" (without quotes) or "M" (without quotes)?

import java.util.*; public class Pesoideal {

public static void main(String[] args) {
    // TODO Auto-generated method stub
    String genero = "";
    int altura = 0;

    do{
         genero = JOptionPane.showInputDialog("Introduce tu género: H o M");

    }while(genero.equalsIgnoreCase("H")==false && genero.equalsIgnoreCase("M")==false);

    if(genero=="H"){
        altura = Integer.parseInt((JOptionPane.showInputDialog("Introduce tu altura:")));
        int pesoideal = altura - 120;

        System.out.println("Su peso ideal sería " + pesoideal + " kg ");

    }
    else if(genero=="M"){
        altura = Integer.parseInt((JOptionPane.showInputDialog("Introduce tu altura")));
        int pesoideal = altura - 110;

        System.out.println("Su peso ideal sería " + pesoideal + " kg ");
    }
}