Followed the below steps from SDCCN FAQ (SAP Note: 763561) and resolved the issue:
6. Q: When trying to create a task in SDCCN an error message appears:' No action possible '. Why can the task not be created?
A: SDCCN has not yet been initialised correctly, and so the customizing for the tasks has not been filled yet.SDCCN can be initialised locally by following these steps:Ensure that the task processor job is deactivated, via
SDCCN -> Goto -> Settings -> Task processorThen initialise the tool via SDCCN ->Utilities -> Activate.