Part is detached from the pallet automatically


In my process modeling I have an issue as below;
After attaching the part to the pallet, part attached pallet flow through the conveyor.
But suddenly the part is detached from the pallet by itself.
I think the part is attached on the conveyor.
I don’t know how to solve this issue.
Please help me.

My guess is that if you are grabbing and releasing it with e.g. a robot it might attach it to wrong object when releasing.

Also seems that you have a ChangeType for the parent product, maybe that doesn’t retain the child attachment?

Thanks for your reply. I’ve find the root cause.
I’ve used assign statement as ProductIn==Null to use while statement.
And this made the definition of the ProductIn vague.
After deleting the assign statement. It is ok now.
For a while statement, I moved related sequence to the other process statement.

Thank you.