With version 2020-04 suddenly posting to orders.json we are seeing 403 errors with the error message:
[response] => Array ( [errors] => Service is unavailable.
(write_orders permission is granted). This happens consistently for the order being synced but not consistently for all of the orders for this user.
Does anyone have any idea what the cause might be?
Can you provide us an x-request-id response header for one of the calls that results in a 403?
The shop you are attempting to create orders on appears to be dormant, hence the errors you are seeing. I would suggest contacting the shop owner for more details.