How to get an API Key?

The docs say: "Holidu will provide you with an api key that you need to verify all your calls. You can also use this api key in the reference section (1) and test all calls in real time."

But silence about how to get an API key. I found out via this forum, that I need to write an mail to [email protected] which I did last week. I got a question about the purpose of my API connection back, which I answered immediately but did not heard anything back. I asked in a follow-up about the status of my request but nothing.

Why do you make it such a intransparent process to get an API key?