Passing Function With Parameters in Context in React

Question

I have Function With Parameters in Context File and the Parameters need to pass it onClick, But it's show error "onLogin is not a function"

Context.js

export const AuthContext = createContext(undefined);

export default Context({children}) {
    const CheckUser = (Username, Password) => {
        const Data = {
            email: Username,
            password: Password
        }
        API.post('/login', Data)
            .then( response => {
                console.log(response.data);
            })
            .catch( error => {
                console.log(error.message);
            })
    }

    <AuthContext.Provider value={{onLogin: CheckUser}}>
        {children}
    </AuthContext.Provider>
}

Child.js

const onLogin = useContext(Context);
const [username, setUsername] = useState('');
const [password, setPassword] = useState('');

<form>
     <TextField onChange={e => setUsername(e.target.value)} />
     <TextField onChange={e => setPassword(e.target.value)} />
     <Button onClick={() => onLogin(username, password)}>Login</Button>
</form>