Please verify that the product in stock and has a price.
If that doesn’t solve it, please:
– Send me the url to the free product
– Send me the coupon code.
– Temporarily enable settings > WooCommerce Extended Coupon Features > Debug mode (then I can see the coupon settings by adding ?wjecf_dump=coupon_code to the url)
I actually need the coupon to apply to any product. So it should work like this, if you purchase any $60 worth of products, you get a free diploma and bag. So all the products are in stock and have prices.