diff --git a/src/main/java/org/gcube/vremanagement/executor/persistence/orientdb/OrientDBPersistenceConnector.java b/src/main/java/org/gcube/vremanagement/executor/persistence/orientdb/OrientDBPersistenceConnector.java
index 320c682..ff88b72 100644
--- a/src/main/java/org/gcube/vremanagement/executor/persistence/orientdb/OrientDBPersistenceConnector.java
+++ b/src/main/java/org/gcube/vremanagement/executor/persistence/orientdb/OrientDBPersistenceConnector.java
@@ -348,8 +348,10 @@ public class OrientDBPersistenceConnector extends
 			}
 
 			RunOn runOn = ScheduledTask.generateRunOn();
-			String json = mapper.writeValueAsString(runOn);
-			doc.field(RUN_ON, json);
+			
+			ODocument runOnDocument = new ODocument();
+			runOnDocument.fromJSON(mapper.writeValueAsString(runOn));
+			doc.field(RUN_ON, runOnDocument);
 
 			timestamp = Calendar.getInstance().getTimeInMillis();
 			doc.field(TIMESTAMP, timestamp);