diff --git a/src/event/event_data/delegated/mod.rs b/src/event/event_data/delegated/mod.rs
index e02e2a7..a8d6fbc 100644
--- a/src/event/event_data/delegated/mod.rs
+++ b/src/event/event_data/delegated/mod.rs
@@ -1,5 +1,5 @@
 use super::{DummyEvent, EventData};
-use super::{InceptionEvent, RotationEvent};
+use super::InceptionEvent;
 use crate::{
     derivation::self_addressing::SelfAddressing,
     error::Error,
diff --git a/src/event_message/attachment.rs b/src/event_message/attachment.rs
index a2d9e36..a03d465 100644
--- a/src/event_message/attachment.rs
+++ b/src/event_message/attachment.rs
@@ -50,7 +50,7 @@ impl FromStr for Attachment {
                     Err(Error::SemanticError("Can't parse counter".into()))
                 }
             }
-            _ => Err(Error::DeserializeError("Unknown prefix code".into())),
+            _ => Err(Error::DeserializeError("Unknown counter code".into())),
         }
     }
 }