You've heard part of Selma's story. She fled Syria with her parents and came to Germany. They live in a refugee shelter. Since their application for political asylum has yet to be decided, they are not allowed to travel around Germany as they like. A Residenzpflicht (compulsory residence) applies to asylum seekers in Germany. This law stipulates that they are to remain within the area of their responsible authority. It's up to each individual state whether that means a particular city, a larger region or even the entire state.
Recognized refugees are allowed to travel freely, but often they're not entitled to decide where they live. They are subject to the Wohnsitzauflage (residence requirement). This is a regulation determining where a person may live, and is intended to distribute refugees evenly throughout Germany.