Laravel/Php - Modify the collection in eager loading closure?

Question

I'm trying to modify this query:

The function of the helper class returns me the products left by removing the amounts used in sales, etc. It works fine if I use dd() inside the function. However, the $products collection isn't changed, what am I missing to successfully modify the base $products array with the collection returned by the helper?

If it helps, here is the helper class:

If there is a better way to handle this, I am glad for every suggestion.

Best regards

Edit:

I've tried the answer in the comment to pass the helper as closure parameter but still no luck.

Answer 1

I think you have to add a return inside the with orders function

return Helper::calculateNumberOfQuantityLeftPerOrder($query->get());