I am Rajinder and while implementing this plugin I found out that it is not able to detect the time zone of +03:30 and -03:30 offset.
Issue #38 was marked as a duplicate of this issue.
-03.30 Is America/St_John and +03.30 is Asia/Teheran.
Both seem to work for me? Can you provide more info, such as which browser, OS etc?