Simple idea to apply in Rules Engine
All we need is a one more condition in order section - "channel name" but also we can use existing "email address" at the moment.
Using the condition we matches one of email addresses or channel name - where we have an issue with the buyer before (we updating the list manually)
Currently there are only two actions available in the rules engine editor:
1. assign order to folder (created in folder manager)
2. assign postal service to order
We need an extra action like: "change order status" where we have selection of action like put the order on hold, cancel order etc.
This solution can mark the orders placed by the buyers in the paste where we have issues with them.
Please see attached images.