If your original Sumdog teacher account was registered using a different email address from your school email account, it would not have been recognised by your district administrators as an existing teacher account, and will have been removed from the School account.
Don't worry though, you will still have access to your teacher account and students. You will need to login with your teacher email address which is listed in Clever. You should have received an email from us to that email address asking you to create a password.
However, if you notice that you are still no longer part of your school account, contact our support team at email@example.com. Do let us know the name of your school and the zip code in your email.