How do I combine items to be in the same subscription order?

Subscription items that have the same order date, shipping address, billing address and payment method will ship as one order.

If you’ve added additional Subscription items and want to make sure
they ship in the same order, simply visit the 'Upcoming Order' tab in
the Subscription section of My Account and amend to make the delivery
dates match. (Also, please confirm the orders have the same shipping
address, billing address and payment method.)

Jun 5, 2020