You can find them in your domain’s settings in Mailgun.
See also: «Mailgun Help Center» → «General» → «Sending Email» → «Where can I find my API key and SMTP credentials?»
You can find them in your domain’s settings in Mailgun.
See also: «Mailgun Help Center» → «General» → «Sending Email» → «Where can I find my API key and SMTP credentials?»