This problem is complex to understand, I leave more than one gif since I have recording limit. (I recommend entering the product page to understand it)
When you select an attribute of the product but DO NOT add text to the REQUIRED field, it shows you a message that you fill in all the fields, as is obvious, so far so good.
The problem arises when you suddenly fill in the text field just after doing what I said before, you get the same error again and again, and if you update the page and do it all the first time? That is, you select the attribute and BEFORE adding to the cart, fill in the text field with text, and as it is obvious the page will tell you that it has been added correctly to the cart, but the surprise is when you arrive at the cart, they were added to the cart also the products that showed error
GIF’s
[video src="https://i.gyazo.com/53606cc330a3180aab4bd81bb1967a18.mp4" /]
[video src="https://i.gyazo.com/b7a86634f80131368a481182fe65ad26.mp4" /]
[video src="https://i.gyazo.com/6f6ac7c28fb9d52a44ede881797637c2.mp4" /]