diff --git a/src/routes/auth.rs b/src/routes/auth.rs
index 39bdc47..a485efb 100644
--- a/src/routes/auth.rs
+++ b/src/routes/auth.rs
@@ -1,7 +1,7 @@
 use axum::{
     extract::State,
     http::StatusCode,
-    response::Json,
+    response::{IntoResponse, Json, Response},
     routing::{get, post},
     Router,
 };
@@ -33,14 +33,35 @@ pub fn router() -> Router<Arc<AppState>> {
 async fn register(
     State(state): State<Arc<AppState>>,
     Json(user_data): Json<CreateUser>,
-) -> Result<Json<UserResponse>, StatusCode> {
-    let user = state
-        .db
-        .create_user(user_data)
-        .await
-        .map_err(|_| StatusCode::BAD_REQUEST)?;
-
-    Ok(Json(user.into()))
+) -> Response {
+    match state.db.create_user(user_data).await {
+        Ok(user) => {
+            let user_response: UserResponse = user.into();
+            (StatusCode::OK, Json(user_response)).into_response()
+        }
+        Err(e) => {
+            tracing::error!("User registration failed: {}", e);
+            
+            // Check for specific database constraint violations
+            let error_message = if e.to_string().contains("users_username_key") {
+                "Username already exists"
+            } else if e.to_string().contains("users_email_key") {
+                "Email already exists"
+            } else if e.to_string().contains("duplicate key") {
+                "User with this username or email already exists"
+            } else {
+                "Registration failed due to invalid data"
+            };
+            
+            (
+                StatusCode::BAD_REQUEST, 
+                Json(serde_json::json!({
+                    "error": error_message,
+                    "details": e.to_string()
+                }))
+            ).into_response()
+        }
+    }
 }
 
 #[utoipa::path(
diff --git a/tests/admin_functionality_tests.rs b/tests/admin_functionality_tests.rs
index d45ebd0..c0cf446 100644
--- a/tests/admin_functionality_tests.rs
+++ b/tests/admin_functionality_tests.rs
@@ -84,8 +84,9 @@ impl AdminTestClient {
             .duration_since(std::time::UNIX_EPOCH)
             .unwrap()
             .as_millis();
-        let username = format!("user_test_{}", timestamp);
-        let email = format!("user_test_{}@example.com", timestamp);
+        let random_suffix = uuid::Uuid::new_v4().simple().to_string()[..8].to_string();
+        let username = format!("user_test_{}_{}", timestamp, random_suffix);
+        let email = format!("user_test_{}@example.com", random_suffix);
         let password = "userpassword123";
         
         // Register regular user
@@ -103,7 +104,9 @@ impl AdminTestClient {
             .await?;
         
         if !register_response.status().is_success() {
-            return Err(format!("User registration failed: {}", register_response.text().await?).into());
+            let status = register_response.status();
+            let error_text = register_response.text().await.unwrap_or_else(|_| "Unknown error".to_string());
+            return Err(format!("User registration failed with status {}: {}", status, error_text).into());
         }
         
         // Login user
@@ -478,8 +481,9 @@ async fn test_admin_user_management_without_roles() {
         .duration_since(std::time::UNIX_EPOCH)
         .unwrap()
         .as_millis();
-    let username = format!("role_test_user_{}", timestamp);
-    let email = format!("roletest_{}@example.com", timestamp);
+    let random_suffix = uuid::Uuid::new_v4().simple().to_string()[..8].to_string();
+    let username = format!("role_test_user_{}_{}", timestamp, random_suffix);
+    let email = format!("roletest_{}@example.com", random_suffix);
     
     let regular_user = client.create_user(&username, &email, UserRole::User, true).await
         .expect("Failed to create regular user");