Not sure what you registered, but right now "munchen.us" is available.
Your location says Albania, do you have a valid .US presence? If someone reports an "invalid registration" to Neustar, as part of their contract with the DOC they have to investigate it. Doesn't happen much now, but if the value of .US domains reaches a significant level you can be sure that it will happen a lot.
Lastly, how many people do you think will be looking for Munich.us ? Let alone "Munich.us" in German? If your answer is a lot, then register it. Mine isn't.