Although stasi is already plural so she didn't need to add the "S" on the end to make it plural.
WikipediaThe Ministry for State Security (German: Ministerium für Staatssicherheit, MfS) or State Security Service (Staatssicherheitsdienst, SSD), commonly known as the Stasi (IPA: [ˈʃtaːziː]), was the official state security service of the German Democratic Republic (East Germany). It has been described as one of the most effective and repressive intelligence and secret police agencies ever to have existed. The Stasi was headquartered in East Berlin, with an extensive complex in Berlin-Lichtenberg and several smaller facilities throughout the city. The Stasi motto was Schild und Schwert der Partei (Shield and Sword of the Party), referring to the ruling Socialist Unity Party of Germany (Sozialistische Einheitspartei Deutschlands, SED) and also echoing a theme of the KGB, the Soviet counterpart and close partner, with respect to its own ruling party...
https://en.wikipedia.org/wiki/Stasi[https://en.m.wikipedia.org/wiki/Stasi]
Seriously though kudos to her for being a teenager and following her dreams. She'll get better over time and maybe someday she'll write the great American novel.