Unable to create account, could that username be offensive and not allowed?

I've been trying to register on Twitch for a long time. But it doesn't work, it always says: "Account can't be created. This username could be offensive and is not allowed." Finally, after 3 times, you get: "You create new accounts too quickly, try again later". That comes after every new username and the thing is I haven't created an account at all, why does it come down to me that I'm opening new accounts too quickly xD. Can someone help me there?

Your nick might indeed be offensive. Why don't you choose another nick? Nothing could be easier than that!

I thought so too, tried everything through. I don't know if "DeNiggi" is a hurtful name in another language or something. In any case, I have half the dictionary through what everything fits together with "Niggi" or "DeNiggi" everything like that