The Code

function getValues() {
    // get the text out of the input and assign it to a variable
    let message = document.getElementById('userInput').value;

    // clean up the values as needed by using regex
    let regex = /[^a-zA-Z0-9]/g;
    let cleanInput = message.replaceAll(regex, '');

    // validate input and make sure its not empty
    if (cleanInput.length == 0) {

        Swal.fire(
            {
                backdrop: 'error',
                backdrop: false,
                //replace this with that variable
                text: 'Please enter a string to check'
            }
        );

    } else {

        // pass the user input to reverseMessage function and
        // assign it's return to a variable
        let revMsg = reverseMessage(cleanInput);

        //send the message adn reverse message to checkForPalindrome
        let palindrome = checkForPalindrome(cleanInput, revMsg);

        // give th results to display messare
        displayResults(cleanInput, revMsg, palindrome);

    }
}

// reverse the string
function reverseMessage(input) {

    // define return
    let output = '';

    for (let i = input.length - 1; i >= 0; i--) {
        output += input[i];
    }

    return output;

}

// check to see if the strings match

function checkForPalindrome(msg, revmsg) {
    if (msg == revmsg) {
        return true;
    } else {
        return false;
    }

}

function displayResults(msgEntered, revMsg, PalTrueFalse) {

    if (PalTrueFalse == true) {
        document.getElementById('msg').textContent =
            `Your message of ${msgEntered} is a palindrome!`;
    } else {
        document.getElementById('msg').textContent =
            'Sorry, but your message is not a palindrome';
    }

}