Hi, please can any one help me on how to unlock my IPHONE, since i bought it i have not being able to use it because any time i put sim card it always ask for pin code.

You can get your iPhone unlocked from Network lock using Remote unlocking method. Which is the safe and secure method to unlock iPhone. You can get this service at low cost from TheUnlockSpot.com here you need to specify your country, Network name to which it is locked, IMEI number of your iPhone. Here they unlock your iPhone using latest versions of iTunes. This is permanent unlocking solution iPhone. Both upgrading and downgrading will not lock your iPhone again.