Thank you for the provided call stack.
I am afraid that it is difficult to tell what might be the reason for the described exception without being able to replicate it on my end. May I ask you to share a sample project demonstrating the scenario along with some sample steps, which I can follow on my end? This will hopefully allow me to reproduce the same behavior and investigate it.
On a side note, you can open a new support ticket and attach a project in it, since project files cannot be attached to forum posts.
Thank you in advance for any help you can provide.
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