[Plugin: WooCommerce] Not saving/displaying Product Variation Data

When I create a product it does not display the variation data. I’ve come to the conclusion that something isn’t working properly in the database.

In all the products that display variations there is an entry in the database like this;

option name
_transient_woocommerce_product_children_ids_(product_id)

option_value
a:3:{i:0;s:4:"1655";i:1;s:4:"1656";i:2;s:4:"1657";}

When I add a new product (that doesn’t display its variations) I look into the database and get an option_value like this;

a:0:{}

If I duplicate a product with non-displaying product variations, it will show the variations on the duplicated product page and add the proper entry into this field;

_transient_woocommerce_product_children_ids_(product_id)

Any thoughts on why it is doing this and how I can fix it, so I don’t have to duplicate a product each time I add a new one?