When we announced our first Kirby Konf, I started a conference profile for it on Colloq: https://colloq.io/events/kirby-konf/2020/mainz/1
I thought initially, that it would be enough to get a list of attendees there. We wanted to keep it simple. But the list of attendees quickly grew larger than expected and I realized that there’s no way to close the list or contact those who are on the list.
That’s why I built an official conference site for it and started a proper ticket registration: https://getkirby.com/konf We announced it on all channels and the 50 available tickets were gone in just two days. Unfortunately, there are still a few who are on the Colloq list, but didn’t manage to get a final ticket. The space at the venue is limited and we cannot add more tickets afterwards. I’m really sorry!
I wanted to use this post to apologize for my beginner mistake. 
You can and should still add yourself to the waiting list though: https://getkirby.com/konf There’s always a chance that someone with a ticket cannot make it to the event.
– Bastian