diff --git a/crates/oxidetalis/src/database/user.rs b/crates/oxidetalis/src/database/user.rs
index 3230aa3..4cc27a0 100644
--- a/crates/oxidetalis/src/database/user.rs
+++ b/crates/oxidetalis/src/database/user.rs
@@ -53,7 +53,7 @@ impl UserTableExt for DatabaseConnection {
         .await
         {
             if let Some(SqlErr::UniqueConstraintViolation(_)) = err.sql_err() {
-                return Err(ApiError::DuplicatedUser);
+                return Err(ApiError::AlreadyRegistered);
             }
         }
 
diff --git a/crates/oxidetalis/src/errors.rs b/crates/oxidetalis/src/errors.rs
index 95f6b2f..325cfc3 100644
--- a/crates/oxidetalis/src/errors.rs
+++ b/crates/oxidetalis/src/errors.rs
@@ -48,7 +48,7 @@ pub enum ApiError {
     RegistrationClosed,
     /// The entered public key is already registered (400 Bad Request)
     #[error("The entered public key is already registered")]
-    DuplicatedUser,
+    AlreadyRegistered,
     /// The user entered two different public keys
     /// one in the header and other in the request body
     /// (400 Bad Request)
@@ -62,7 +62,7 @@ impl ApiError {
         match self {
             Self::SeaOrm(_) => StatusCode::INTERNAL_SERVER_ERROR,
             Self::RegistrationClosed => StatusCode::FORBIDDEN,
-            Self::DuplicatedUser | Self::TwoDifferentKeys => StatusCode::BAD_REQUEST,
+            Self::AlreadyRegistered | Self::TwoDifferentKeys => StatusCode::BAD_REQUEST,
         }
     }
 }