diff --git a/paper/client.py b/paper/client.py
index 07d365c..32ca1d1 100644
--- a/paper/client.py
+++ b/paper/client.py
@@ -23,7 +23,8 @@ from telethon.errors.rpcerrorlist import (
     UsersTooMuchError,
     UserChannelsTooMuchError,
     UserIsBlockedError,
-    YouBlockedUserError
+    YouBlockedUserError,
+    UsernameInvalidError,
 )
 
 class PaperClient(TelegramClient):
@@ -93,11 +94,13 @@ class PaperClient(TelegramClient):
         return await super().get_participants(group, *args, **kwargs)
 
     async def __cast_to_entity(self, entity: Entity | EntityLike) -> Entity:
-        if not isinstance(entity, Entity):
-            if hasattr(entity, "username"):
-                entity = await self.get_entity(entity.username)
-            else:
-                entity = await self.get_entity(entity)
-
-        return entity  # type: ignore
+        try:
+            if not isinstance(entity, Entity):
+                if hasattr(entity, "username"):
+                    entity = await self.get_entity(entity.username)
+                else:
+                    entity = await self.get_entity(entity)
 
+            return entity  # type: ignore
+        except UsernameInvalidError as e:
+            raise IgnoreException(e)