After setting a Ticket to Closed, you have noticed that the Sales Order header field is still editable
SAP Cloud for Customer
This is an expected behavior, based on the feature original design. This happens because the users might miss to associate the Ticket to the Sales Order before closing the ticket, or associate the Ticket to the wrong Sales Order. With this feature user can associate the ticket to the Sales Order even after it closed just in case they forget to add it in the initial stage.
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