JSFiddle - React, Tailwind, and code Playground

HTML

<input class="dateValue" />
<input />

JavaScript

$('input.dateValue').on('blur', function(event)
{
    if ( ! /(\d){4}$/.test(this.value) )
    {
        var $this = $(this).val('');
        
        setTimeout(function (){
            $this.focus();
        }, 0);
    };
});