Do I need to unlock my apple iphone?

Apple will always address you by your name or the name they have on file for you, not Dear Customer, Dear Client or by using your e-mail address.  The e-mail will be from @apple.com or @iTunes.com. E-mail addresses can be spoofed. You can go to Mail/View/Message/Show all Headers to see more. Apple emails won't have poor grammar/misspellings. Apple e-mails will never contain an attachment. 

The email undoubtedly was a scam. Apple does not send such emails. You are good to go unless you provided some sensitive information (e.g., your Apple ID password, your social security number, a credit card number, etc.) to the scammer. If you did provide sensitive information, then post back.