Why Material UI Theme overrides doesn't work?

Question

I use the material UI "createTheme" function. When ı write overrides for button and switch it's doesn't work. Material UI's None of the overrides features work but the theme palette, font-size working. Why it doesn't work? Thanks in advance. // My overrides

 overrides: {
      MuiButton: {
        primary: {
          background: "pink",
        },
        sizeSmall: {
          height: 22.5,
          fontSize: 10,
          padding: "0 15px",
        },
        sizeLarge: {
          height: 37,
          padding: "0 30px",
          fontSize: 16,
        },
        text: {
          background: "#1AD971",
          borderRadius: 4,
          border: 0,
          color: "white",
          padding: "0 22px",
          height: 30,
          textAlign: "center",
          lineHeight: 1,
          fontSize: 14,
          fontWeight: 400,
          "&:hover": {
            backgroundColor: "#0BBF5D",
          },
        },
        contained: {
          backgroundColor: "#FFFFFF",
          color: "#000000",
          borderRadius: 30,
        },
        outlined: {
          color: "#1AD971",
          border: "1px solid #1AD971",
          borderRadius: "15px",
        },
      },
      MuiSwitch: {
        switchBase: {
          color: "#73889D",
        },
        colorSecondary: {
          "&$checked": {
            color: "#FFFFFF",
          },
        },
        track: {
          opacity: 1,
          backgroundColor: "#213348",
          "$checked$checked + &": {
            opacity: 1,
            backgroundColor: "#FFC231",
          },
        },
      },
    },

Answer 1

If you are working on MUI version 5, as mentioned in the comment above, you should be using the below code

const theme = createTheme({
  components: {
    MuiButton: {
        styleOverrides: {
            root: {
                border: '1px solid #ff4742',
                background: 'white',
                borderRadius: 12,
                border: 0,
                color: 'black',
                height: 48,
                padding: '0 30px',
                fontWeight: 'bold',
                boxShadow: '1px 2px 4px rgb(0 0 0 / 10%)',
            }
        }
    },
}});