This is a known issue with Dynamo Player for C3D and how it handles element bindings. The behavior you experience in the Dynamo UI is by design so that duplicate objects are not created every time the script is run. However, the behavior with Dynamo Player is unpredictable. There are several other related posts (see below). As far as I know, there is still no acceptable solution for fixing this behavior in Dynamo Player. The best I have been able to come up with is mentioned here.