Date picker not displaying year properly with Fluent Form Pro Addon

I am using the below code for date picker condition:
{
maxDate: new Date(new Date().getFullYear() – 18, 11, 31), // 18 years ago from today
allowInput: true,
dateFormat: “m/d/Y”,
onReady: function(selectedDates, dateStr, instance) {

// Set the width, top position, and padding for the Flatpickr calendar directly via JavaScript

//I use this for the date picker issue.
instance.calendarContainer.style.width = “450px”; // Adjust as needed
instance.calendarContainer.style.padding = “10px”; // Add padding around the calendar
instance.calendarContainer.style.zIndex = “9999”; // Ensure it’s above other elements
instance.calendarContainer.style.position = “absolute”; // Ensure proper positioning

    // Add event listener to format input as the user types
    instance.input.addEventListener('input', function(e) {
        let value = instance.input.value.replace(/[^\d]/g, ''); // Remove non-digits
        if (value.length > 8) {
            value = value.slice(0, 8);
        }

        let formattedValue = '';
        if (value.length > 2) {
            formattedValue += value.slice(0, 2) + '/';
            value = value.slice(2);
        }
        if (value.length > 2) {
            formattedValue += value.slice(0, 2) + '/';
            value = value.slice(2);
        }
        formattedValue += value;
        instance.input.value = formattedValue;
    });
}

}

The year isn’t showing nonetheless. Need help

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