Hello Dũng.
Simply speaking, the following 3 incident fields should be set at a time.
incident.resolution_id = "Resolved"
incident.resolution_summary = "Resolved"
incident.plan_status = "C"
Since incident.resolution_id is select type, its value should match the possible candidate. (just in case your orglocale is other than en)
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Yohji Amano
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