Admin can customize add to cart, cart page and category level error messages.
Add to Cart Error Messages
Customize the error messages which will be display when product is added to cart.
Cart Page Error Messages
Customize the error messages which will be display on cart page.
Category Error Messages
Customize the error messages which will be display on cart page for Category rules.
You can use following shortcodes to customize error message
{product_title}
{min_qty}
{max_qty}
{min_order_qty}
{max_order_qty}
{min_order_value}
{max_order_value}
{min_order_items}
{max_order_items}
{cart_qty}
{group_of_qty}
{product_required_qty}