Hi Nicolas,
I actually deleted my custom configuration and also reset the standard configuration but still the issue persists.
Anyway, now the issue is fixed. What I did is after checking each and every part of the View Configuration from Component Workbench, finally gone to the configuration from AET the same way how we created and changed the text there. Surprisingly, this has fixed all issues and now the configuration settings are working as desired.
So not sure if I am correct but from what I have seen, if we add any field using AET then do all changes for that field including label etc from AET itself rather than from View Configuration.
Thanks all for your time and Special thanks to Nicolas!!.
Thanks & Regards,
Raja Sekhar K