Hi Kittu
Most often it means that the condition of your action is not "ok". So you should check SPRO "Define Conditions" under IT Service Management and check that the condition for the action that is not displayed is met. I would think it isn't. It can be due to those other issues you're mentioning since that's not normal either. Most actions have "errorfreeflag"=X and once errorfreeflag is not "ok", you won't see the action since there is an issue with the CD.
Best regards
Tom