In case your matter is about billing breakdown or you need to review your billing history, these are always available on the Nosto admin. On the admin panel you can also download all your invoice history as pdf-files.
On other topics, you can either contact Support through the chat available on the Nosto admin, which also identifies you as a user making it the preferable way to leave a message. In case this is not possible, you can also leave a message on our website or by emailing your inquiry to billing@nosto.com. Please state your account id an name in the communication.