The discount is not showing

I am using “WooCommerce PDF Invoice Builder” to generate invoices and Atum Inventory for inventory management. However, the invoice is not showing the discount amount, regular price, or discounted price.

I contacted the plugin developer, and they replied:

“The plugin doesn’t perform the calculations; it’s WooCommerce that does. The plugin simply uses whatever data WooCommerce provides. The plugin you’re using might have its own method for calculating those amounts instead of using the standard WooCommerce system.

For example, the plugin uses WooCommerce’s standard wc_order method ‘get_discount_total’ to retrieve the discount total.”

I would like to know how I can display the discount amount, regular price, and discounted price on the invoice.