diff --git a/examples/toy-chat/src/protocol.rs b/examples/toy-chat/src/protocol.rs
index 4158f06..dbcb300 100644
--- a/examples/toy-chat/src/protocol.rs
+++ b/examples/toy-chat/src/protocol.rs
@@ -37,6 +37,6 @@ impl Chat2Message {
     }
 
     pub fn timestamp(&self) -> DateTime<Utc> {
-        Utc.timestamp(self.timestamp as i64, 0)
+        Utc.timestamp_opt(self.timestamp as i64, 0)
     }
 }