9 day delay on essential equipment due to single item that was available

Order ***5 I have received a mail for a delayed order. I have essential equipment required to work remotely but this is being delayed by over a week for a single item. Within the mail is a 'Manage Order" link. How do I manage my order? Am I able to remove items that are now delaying my order? Customers cant actually manage completed orders now can they? Why can you not manage the order and split the items?