Help to unlock for iPhone 4

Apple will not unlock phones. It has to be done through the carrier which may or may not be willing to do so (apparently 'no' in your case).  It may be difficult to get a refund on the phone now.  Frankly the whole changing countries thing and uncertainties and difficulties about a phone being locked or unlocked is a bit of a nightmare with iPhones in my opinion, and an iPhone is one of the things I would not risk buying used.

Apple can do nothing to help you. Only the carrier to whom the iPhone is locked can unlock it. Bell Canada does not offer unlocking services, so there's no way to get your iPhone officially unlocked. Your best option may be to sell your iPhone to someone in Canada and then buy an unlocked iPhone.

By the way, please be aware that you are not communicating with Apple when you post in these forums. The only people who will reply to your posts are we your fellow users.

Regards.

Thank all.

I'll think to sell to someone in Canada and then buy an unlocked iPhone.