AddToCart before all (required) fields are filled

Filling the “personalization” field on a product is required.
Product can only be put into cart after this field has been filled.

GTM4WP Plugin pushed Event into datalayer when user clicks on Add to Basket button regardless of this field being filled or not.

So our “AddToCart” Values are inflated.

https://kakaloo.de/produkt/schluesselanhaenger-two-holz-senfgelb

What can be done?

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