WooCommerce add to cart validation: prevent add to cart

Question

I have a probleme with woocommerce that im trying to fix for few days.

I am creating a website for a guy and he wanted me to add a custom input on the product page, I cou

Answer 1

I had this issue and after much trial and error the fix was to adjust the $priority parameter (10 is default) in :

add_filter( 'woocommerce_add_to_cart_validation', 'add_the_date_validation', 10, 5 );

As per usual, I tried everything else first...changed this to 15 and bingo..! I guess it was running ahead of code ranked lower priority, which then let items into cart.