I cant open my face book account ,,its showing expired ,,

What is the exact message that you get?

the following was found on facebooks page here
My login email address is invalid or expired.

1. If you remember your Facebook password, try logging in to your account with any email address or mobile phone number confirmed on your account. Once logged in, you can edit your email addresses from the Settings tab of the Account Settings page.
2. If you do not remember your Facebook password, visit the password resetpage to try to regain access to your account.
   Tip: If you can't identify your account using your email address, try searching for it with your name and a friend's name.