"shan", please read (or at least browse) the JavaRanch display name rule
here.
Disply names must be two words: your first name, a space, then your last name. Fictitious names are not allowed.
Your display name used to be valid, not it is not. Please change it back immediately, since accounts with invalid display names get deleted.
thanks,
Dave.
PS browsing your posts it appears you provide much needed help, it would be a shame if your account were deleted