commerce product display showing only one product when multiples selected

Question

I'm working on a Drupal 7 site using Commerce module.

When adding multiple products to a product display, I'm only seeing a single "Add to cart" button for the first product in the reference field, with no select menu for the additional products.

What's strange is that I did have that showing on the node, but not now - although I've only been changing view templates. Is there some config I should check to make sure this functionality is enabled that I may have inadvertently changed?

How would I ensure that a product display shows multiple products properly?

Answer 1

Check the Display settings for the Product Display type in Structure -> Content -> Product Types, and make sure that the Product field is set to be visible on all view modes.

Set it to "Add to Cart form" and it will display a choice of all applicable products.

Note - I had a duplicate "product" reference field on products which confused the issue, and this was what was displaying the single "add to cart" button.