In last 2.5 months i have requested my adsense PIN twice but don't receive it.
8:16 pm on Sep 25, 2013 (gmt 0)
The higher probability is a problem with your email.
Check your account details and make sure your email address is correct
Some email providers have a bad habit of zapping essential auto generated messages as spam. Make sure that all spam filtering is off. If you are using Hotmail, Yahoo or AOL consider using a different email provider. I usually include Gmail on that list, I would hope that they don't regard themselves as spammers but I wouldn't guarantee it.