I send a mail to “firstname.lastname@example.org” but I have no response from “email@example.com”
Sending in a support request generates an automatic receipt email confirming that you request has been obtained, and provides you with a ticket ID. If you did not get that email address. If you did not receive that then your email account may be blocking either the send or receipt of the email.
Please confirm you do or do not have a ticket ID.
Additionally, please do not publicly share your personally identifying information, like your email address, in our forums. Anyone can read posts here.
Lastly, a purchase does not require an account. If you want to look up an existing purchase by email address you can use the following page: https://itch.io/docs/buying/already-bought