Hi Robi, I thought about this also when I joined here. I want to change my username and want a hotshot one. But I guess I'm late, reaching this far and going back again would be a disaster for me. In my experience in exploring here in my profile would be not possible. You have to pay as they said but the most important is asking permission to the authoring devs. here. So the easiest way to solve your problem or answer your question would be to make a new account with your desired username and that's it.