React Material UI: Appbar gave TypeError: Cannot read properties of undefined (reading '100&#03-CodePudding

I am making a multi step form for which I was using Material UI component. But the moment I import it, it shows error. The code is:

import React from 'react';
import { ThemeProvider } from '@mui/material/styles';
import AppBar from '@mui/material/AppBar';
import Toolbar from '@mui/material/Toolbar';
import Typography from '@mui/material/Typography';

function FormUserDetails({ nextstep, values }) {

    const proceed = (e) => {
        e.preventDefault();
        nextstep();
    }
    return (
        <ThemeProvider>
            <React.Fragment>
                <AppBar position="static">
                    <Toolbar>
                        <Typography variant="h6" component="div" sx={{ flexGrow: 1 }}>
                            News
                        </Typography>
                    </Toolbar>
                </AppBar>
            </React.Fragment>
        </ThemeProvider>
    )
}

export default FormUserDetails

Now the error looks like this: `

TypeError: Cannot read properties of undefined (reading '100') (anonymous function) C:/Users/edkni/Documents/projects/multi-step form/state_form/node_modules/@mui/material/AppBar/AppBar.js:40
37 | theme,
38 | ownerState 39 | }) => { 40 | const backgroundColorDefault = theme.palette.mode === 'light' ? theme.palette.grey[100] : theme.palette.grey[900]; 41 | return _extends({ 42 | display: 'flex', 43 | flexDirection: 'column',View compiled transformedStyleArg C:/Users/edkni/Documents/projects/multi-step form/state_form/node_modules/@mui/system/esm/createStyled.js:175 172 | } = _ref2, 173 | other = _objectWithoutPropertiesLoose(_ref2, _excluded3); 174 | 175 | return styleArg(_extends({ 176 | theme: isEmpty(themeInput) ? defaultTheme : themeInput 177 | }, other)); 178 | };

I have no idea what that means. It would be great help if someone could answer. Thank you in advance.

CodePudding user response：

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