Hello Marcus,
You are using a plugin for your additional product fields, Booking Activities may not be compatible with it.
If you use Advanced Forms to add fields, the cart items are not merged because Booking Activities knows that the additional fields have different values.
Else, when a user adds the same event to cart, the old cart item is merged with the new one and the quantity increases. Booking Activities doesn’t know about the additional fields.
You can disable the merging by code, for example add this code to your child theme functions.php or with Code Snippets to never merge cart items:
add_filter( 'bookacti_merge_cart_item', '__return_false', 100 );
Ideally, replace '__return_false'
with a function where you check if the additional fields have the same values and return false only if they are different.