Flow Designer Error : Error occured while inserting record: null

[Apurva Jogal]

Hi all, 
While Creating a HR Request, The flow is throwing an error as below screenshot. 

I have checked the flow properties it Runs as as System User. 
And the flow is in Human Resource : Core application. 

Can anyone help with how to resolve this error?

[DrewW]

If you click the "Create Record" just above that you should see more detail that should lead you to something.

[Apurva Jogal]

@DrewW It shows values which are set in the activity. 
All values are populated, none of them is null.