diff --git a/frontend/mining-app/lib/core/network/api_client.dart b/frontend/mining-app/lib/core/network/api_client.dart
index 70202f29..98461bed 100644
--- a/frontend/mining-app/lib/core/network/api_client.dart
+++ b/frontend/mining-app/lib/core/network/api_client.dart
@@ -137,7 +137,8 @@ class ApiClient {
         if (statusCode == 401) {
           return UnauthorizedException();
         }
-        final message = e.response?.data?['error']?['message']?[0] ?? '服务器错误';
+        final messages = e.response?.data?['error']?['message'];
+        final message = (messages is List && messages.isNotEmpty) ? messages[0].toString() : '服务器错误';
         return ServerException(message, statusCode: statusCode);
       default:
         return ServerException(e.message ?? '未知错误');
diff --git a/frontend/mining-app/lib/presentation/pages/c2c/c2c_market_page.dart b/frontend/mining-app/lib/presentation/pages/c2c/c2c_market_page.dart
index f4a2cd66..9a0cc6ee 100644
--- a/frontend/mining-app/lib/presentation/pages/c2c/c2c_market_page.dart
+++ b/frontend/mining-app/lib/presentation/pages/c2c/c2c_market_page.dart
@@ -314,7 +314,7 @@ class _C2cMarketPageState extends ConsumerState<C2cMarketPage>
                   ),
                   child: Center(
                     child: Text(
-                      (order.makerNickname ?? order.makerPhone ?? 'U')[0].toUpperCase(),
+                      ((order.makerNickname?.isNotEmpty == true ? order.makerNickname : null) ?? (order.makerPhone?.isNotEmpty == true ? order.makerPhone : null) ?? 'U')[0].toUpperCase(),
                       style: TextStyle(
                         fontSize: 18,
                         fontWeight: FontWeight.bold,
diff --git a/frontend/mining-app/lib/presentation/pages/c2c/c2c_order_detail_page.dart b/frontend/mining-app/lib/presentation/pages/c2c/c2c_order_detail_page.dart
index 26fc9bf6..87ebc1bd 100644
--- a/frontend/mining-app/lib/presentation/pages/c2c/c2c_order_detail_page.dart
+++ b/frontend/mining-app/lib/presentation/pages/c2c/c2c_order_detail_page.dart
@@ -754,7 +754,9 @@ class _C2cOrderDetailPageState extends ConsumerState<C2cOrderDetailPage> {
           // 发布方
           _buildParticipantRow(
             label: order.isBuy ? '买方 (发布者)' : '卖方 (发布者)',
-            name: order.makerNickname ?? _maskPhone(order.makerPhone ?? ''),
+            name: order.makerNickname?.isNotEmpty == true
+                ? order.makerNickname!
+                : (order.makerPhone?.isNotEmpty == true ? _maskPhone(order.makerPhone!) : '未知用户'),
             isMe: isMaker,
           ),
           const Divider(height: 24),
@@ -762,7 +764,9 @@ class _C2cOrderDetailPageState extends ConsumerState<C2cOrderDetailPage> {
           if (order.takerAccountSequence != null)
             _buildParticipantRow(
               label: order.isBuy ? '卖方 (接单者)' : '买方 (接单者)',
-              name: order.takerNickname ?? _maskPhone(order.takerPhone ?? ''),
+              name: order.takerNickname?.isNotEmpty == true
+                  ? order.takerNickname!
+                  : (order.takerPhone?.isNotEmpty == true ? _maskPhone(order.takerPhone!) : '未知用户'),
               isMe: isTaker,
             )
           else
@@ -791,7 +795,7 @@ class _C2cOrderDetailPageState extends ConsumerState<C2cOrderDetailPage> {
           ),
           child: Center(
             child: Text(
-              name[0].toUpperCase(),
+              name.isNotEmpty ? name[0].toUpperCase() : 'U',
               style: TextStyle(
                 fontSize: 18,
                 fontWeight: FontWeight.bold,