Hello, it would appear that Facebook are reviewing your account for a perceived action that was not in accordance with their Community Standards. Whilst they are doing this review you will be unable to access your account.
You can have a look here at an article on what to do if your facebook account is locked or disabled.
If you feel that your Facebook account has been unjustly deactivated, use the contact form within this article to contact Facebook.
Either way, your Facebook account will remain deactivated until further notice.