I assume you are working with calculations to check the parent incident assignement?
This error message tells you that something is NULL which is not ment to be NULL.
If you are working with calculation, maybe you can show us your calculation here.
Thanks for the feedback. I have been searching on the attributes to find the calculation but i cant seem to find it.
Are you aware if it will be under the Incident module? Currently, the "Child" and "Parent" attributes do not have any calculation associated to them.
I think the calculation that failes is in your process itself.
You can turn on diagnostics logging in configuration center and see which calculation is failing.