Hi Sameeksha!
Thanks for being so patient while we investigated this in Storyline 3 and Storyline 360.
We've now updated our article to include newer versions of Storyline: Storyline 360 and Storyline 3: Let LMS Learners Know When They Lose Their Internet Connection
Currently, this feature only works with Flash output, not HTML5 output. If you're using Storyline 360, you must choose the classic player style and include Flash output when you publish your course.
It sounds like you also have a need to use this feature in HTML5, so I've submitted that feature request on your behalf. If HTML5 support is added in the future, we'll let you know!