In In-Commerce order workflow several checks are made, that check current date versus dates stored in order. For example credit card expiration in order is always checked against current date and not date, when order was submitted.
This creates a problem, when Administrator is cloning an order after date, when credit card used there is expired. In such case validation happens against cloning date and not date, when order was submitted and it fails and order clone isn't created.
Solution:
Only use current date when order is in Incomplete stats.