Why can I not start an operation on this order?

Work through these steps in order, because between them they explain most cases.

1. First, check for a blocking custom state. A custom state is either informative, which is only a label, or blocking, which disables the specific operations listed on it. This is the most common cause and the portal shows a banner when it applies.

2. Second, an order can only have one active operation at a time, so a pending or ongoing delivery, refund or compensation blocks a new one until it settles.

3. Third, starting and restarting operations requires an admin role.

4. Fourth, check that the operation is valid for the current order status, for example that a cancellation is not attempted once a delivery exists.