Update: The issue is resolved.

Currently there is an issue where the Subscriptions Control Center shows the following error:

"STORE UPGRADES IN PROGRESS
Our engineers are performing planned maintenance and ordering is not possible at this time.
Please try again later."

The issue started occurring on August 1.

A fix is targeted for the end of next week, pending successful testing and implementation.

In the meantime, if you need to modify your subscription or have any questions about your subscription, please submit the Online Support Form for assistance specific to your account. We apologize for the inconvenience.