Hi Vaishnavi,
You need to refresh your screen to load the new content as Mahesh and Win said. Only do the ajax refresh will only refresh the screen for the current user. The other screen will not be updated. There are 2 options to do that:
The easiest way is using a javascript to trigger a action that will perform the refresh. You can use this component to make your job easier: https://www.outsystems.com/forge/component-overview/2134/auto-refresh-utils . The only issue in this case is the refresh will happens often even if you didn´'t add new comments.
The other way it is using Firebase: https://www.outsystems.com/forge/component-overview/2121/firebase-web. In this case, you will trigger the refresh only when you really add a new content. It is a better implementation but you need to configure the Firebase to do it.
Best regards
Fabio