My Quantity increase button is not enabling when i reduce my quantity from maximum. I am using ajax for increasing and decreasing quantity in my cart

$(document).ready(function() {
    function updateQuantity(variantId, newQuantity) {
        const basePrice = parseFloat($('#quantity-' + variantId).data('base-price'));
        //const totalPrice = newQuantity * basePrice;

        $.ajax({
            url: '/updateCartItem',
            method: 'POST',
            data: {
                variantId: variantId,
                quantity: newQuantity
            },
            success: function(response) {
                $('#stock-error-' + variantId).remove();
                $('#quantity-' + variantId).text(newQuantity);
                $('#productquantity-' + variantId).text(newQuantity);
                $('#total-price-' + variantId).text(response.prodtotalPrice.toFixed(2));
                $('#total-price-of-all-products').text(response.totalPriceOfAllProducts.toFixed(2));
                $('.total-quantity').text(response.totalQuantity);
                $('.total-price-of-all-products').text(response.totalPriceOfAllProducts.toFixed(2));

                const availableStock = response.stock;

                if (newQuantity >= 5) {
                    console.log('Disabling button for variant: ' + variantId);
                  //Disables the button
                    $('.quantity-increase[data-variant-id="' + variantId + '"]').prop('disabled', true);
                } else {
                    console.log('Enabling button for variant: ' + variantId);
                //Enables the button
                    $('.quantity-increase[data-variant-id="' + variantId + '"]').prop('disabled', false);
                }

                if (response.error === 'Insufficient stock available.') {
                    showErrorMessage(variantId, 'Insufficient stock available. Please reduce the quantity.');
                    $('.quantity-increase[data-variant-id="' + variantId + '"]').prop('disabled', true);
                }
            },
            error: function(xhr, status, error) {
                const response = JSON.parse(xhr.responseText);
                if (response.error === 'Insufficient stock available.') {
                    const errorMessage = '<span id="stock-error-' + variantId + '" class="text-danger">Insufficient stock available. Please reduce the quantity.</span>';
                    $('#quantity-' + variantId).closest('td').append(errorMessage);
                    $('.quantity-increase[data-variant-id="' + variantId + '"]').prop('disabled', true);
                } else {
                    console.error('Error updating cart item:', error);
                    $('.quantity-increase[data-variant-id="' + variantId + '"]').prop('disabled', false);
                }
            }
        });
    }

    $('.quantity-increase').click(function() {
        const variantId = $(this).closest('.quantity-controls').data('variant-id');
        let quantity = parseInt($(this).siblings('.quantity-input').val());
        if (quantity < 5) {
            quantity += 1;
            $(this).siblings('.quantity-input').val(quantity);
            updateQuantity(variantId, quantity);
            $(this).prop('disabled', false);
        } else {
            showErrorMessage(variantId, 'Cannot purchase more than 5 items.');
            $(this).prop('disabled', true);
        }
    });

    $('.quantity-decrease').click(function() {
        const variantId = $(this).closest('.quantity-controls').data('variant-id');
        let quantity = parseInt($(this).siblings('.quantity-input').val());
        if (quantity > 1) {
            quantity -= 1;
            $(this).siblings('.quantity-input').val(quantity);
            updateQuantity(variantId, quantity);
        } else {
            $(this).siblings('.quantity-input').val(1);
            showErrorMessage(variantId, 'Cannot purchase less than 1 item.');
            $(this).prop('disabled', true);
        }
        $('#stock-error-' + variantId).remove();
    });

    function showErrorMessage(variantId, message) {
        const errorMessage = '<span id="stock-error-' + variantId + '" class="text-danger">' + message + '</span>';
        $('#quantity-' + variantId).closest('td').append(errorMessage);
    }

when I increase my quantities in my cart after reaching a limit here 5, then the quantity increase button (+) is disabling and I want to enable that button when the quantity is reduced by using quantity-decrease button. I have given the code to enable and disable based on the quantity, but the button is disabling and when I reduce the quantity it is not enabling the button, it is in the disabled state only