Check the value for the constant
EMPTY_TRASH_DAYS. With this constant can you control how long is the time to save in trash before delete automatically. Check at first the
wp-config.php for this constant, maybe is set in your installation for a small value. The codex write more about the constant and his possibilities.
Also it is possible to change the default via hooks, like
pre_delete_post. A good point to debug is the function
But you write about 'products', maybe you have active a custom post type there add this post type and the enhancement, the plugin have a option for the function, timestamp to delete this post type Product.