diff --git a/hue2mqtt/schema.py b/hue2mqtt/schema.py
index 87026db..e20de5a 100644
--- a/hue2mqtt/schema.py
+++ b/hue2mqtt/schema.py
@@ -77,7 +77,7 @@ class GroupInfo(BaseModel):
     type: str
     state: GroupState
 
-    group_class: Optional[str] = Field(..., alias="class")
+    group_class: Optional[str] = Field(default=None, alias="class")
 
     action: LightState