There are two common causes of a failed account creation.
1) You already have an existing Spitfire account, and should instead use the "Forgot your password?" function to reset your password and sign back into your account.
2) At the time of writing, there is a website bug that gives the error, "We were not able to create a new account". If you see this message, you should try signing in using the credentials that you attempted to use for your account creation, as oftentimes the account was in fact created despite the message.
If you've tried the above and are still unable to access your account, please click the help icon on the bottom right of this page to get in touch with us.