Hello Purva
I have created the Sample Chat Application for you. I have not done this in Your OML because it was showing Dependencies Errors. You can check the Sample I have sent to you in Personal Message
I have allowed the Guest User to see the Application and that's why I have sent this to you in Personal Message because it allow Guest User to enter in my DB. Please Keep it Safe.
When the LoggedIn User Send any message it will show like how MG and NG is showing.
Let me know if that works. I will share the OML with you.