Tutanota e-mail account stopped existing!!

Hi, I created a tutanota e-mail address for somebody two weeks ago and it just seems not to exist anymore: we all get error messages when we try to send e-mails to the address. It is a very big problem since the person gave this e-mail address to many people and they now get this error message. I sent you an e-mail and I hope you will fix it as quickly as possible. Thank you very much. Kind regards.