Help with scriptlet

Hi all,

Trying to use a scriplet in the configuration to get the current date and time which is stored as a variable and I run into this error. Have tried to check for the meaning of the error but can't seem to find it. Capture.JPG

For reference, my script is as follows

Capture.JPG

I'm not sure whether its how I'm trying to call the script or whether its my script itself that's the problem. For now, I'm only trying to debug and will get this error. I couldn't find the flow variable at all which was why I was trying use the debug but got that error.

Just to add on, I have clicked the "Check Script" option which returns me a "No errors found." message.  

Thanks in advance for any help!
David