The "Actions for combined orders" setting determines what happens to an order after it has been combined. By default, the order is deleted, but it is also possible to transfer it to the cancellation status.
If, after selecting the cancellation status, the status was deactivated or transferred to another status group other "Cancel", then the combined orders will be deleted until the status is changed to the current one. Saving settings is also not available. When you try, a message will be displayed notifying that the status is inactive or is in a different group (depending on the situation).
Statuses are created in the section of the same name in the general system administrative settings. Read more in related article.