Serval has lost the ability to speak. According to Black Rhino and White Rhino, it happened due to an illness that's been going around in the Waterfront Area...
We were at a loss when Serval 
lost the ability to speak.
كنّا في حيرةٍ عندما فقدت سارفال
القدرةَ على الكلام
Serval verlor die Fähigkeit zu sprechen und wir wussten nicht mehr weiter.
Que Serval perdiera la capacidad
de hablar nos dejó anonadadas,
Serval était désormais
incapable de parler,
Non sapevamo proprio cosa fare,
quando Serval-san ha perso la capacità di parlare.
Nós não sabíamos o que fazer quando
a Serval-san perdeu a habilidade de falar.
В прошлый раз мы прервались на моменте,
когда Сервал утратила способность говорить.