[SalesForce] Process Builder keeps failing

I am trying to explore this feature.I am doing a simple step : which check if object A is created or edited, it should insert reecords of change into Object B.

But i keep getting the below error: Problem is fields used is of same data type as Object A..and if not then thats a Text field to insert on. What would be your advice on this issue?

System.DmlException: Insert failed. First exception on row 0; first
error: UNKNOWN_EXCEPTION, The record couldn’t be saved because it
failed to trigger a flow.
java.lang.IllegalArgumentException:
unable to find field dataType for complex reference
unable to find
field dataType for complex reference
Contact your administrator
for help.: [] 13:00:50.653 (7653018638)|METHOD_EXIT|

Best Answer

Here the issue was when you map the look up fields which were coming through quite an indirect relation-the process builder kept failing to map even if the datatype matched. Had to sort this by using a formula field-that holds the value from that relation. Then use this formula field in the mapping as an alternative.