Yes, but it probably doesn’t concern you. It only allows the registration of your main place of residence. i.e: You can’t specify you have other addresses in Germany. This is fine for 99% of people moving to Germany as they only have one address usually. Also, since this service is free, it runs on limited server capacity. Please note that you might have to fill in your birthname/former name in manually, in case you register under a new last name.