JSFiddle - React, Tailwind, and code Playground

HTML

<script>
function nameClick(element) {
    alert(element) // See what was your "enabled" variable.
    
    if (element.disabled !== undefined) {
        // You don't have to set it to true, it could be anything else
        // Disables the button
        element.disabled = 'true';
    } else {
        // Will never work because you can't fire the click event of a disabled button but shows you how to re-enable the button if you want to
        element.removeAttribute('disabled');
    }
}
</script>

<button onclick="nameClick(this)" name="FullNameExact" style="height:20%;width:75%;top:5%;left:13%;margin-bottom:5%">FULL NAME EXACT</button>

CSS

button[disabled] {
    background: green;
}