This error usually occurs if the profile picture uploaded is not of the correct file type. Please ensure you are using a JPEG, PNG or GIF. All fields on the initial part of the form must also be filled in with no trailing white spaces.

The email field should also not be editable, as invite is only by email to which the invite was sent to, in this instance if it does appear editable, this would suggest the link is broken/expired and you would need to refer to your admin to delete your current invite and send you a new one.