Does your code have a hyphen in it? If so, please could you remove it and try again? Some phone providers are adding a hyphen to codes that run over two lines of text but they're not part of your Access or Invite code!
The codes are case sensitive so please check the codes carefully when entering into the registration form.
We recommend typing the codes into the boxes on the registration form manually rather than using cut and paste so that no extra characters or blank spaces are entered into the boxes by mistake. Sometimes your device may try to capitalise the first letter of the code so please check if the first letter is lowercase that it still is once you've entered the text.
It may seem obvious but please do make sure that you haven't accidentally added the Access code to the Invite code box!
Finally, if all else fails, please just drop us an email to firstname.lastname@example.org and we'd be happy to investigate further.