diff --git a/app/Http/Controllers/Barobill/EaccountController.php b/app/Http/Controllers/Barobill/EaccountController.php
index adb94227..1b51e9f0 100644
--- a/app/Http/Controllers/Barobill/EaccountController.php
+++ b/app/Http/Controllers/Barobill/EaccountController.php
@@ -949,14 +949,18 @@ public function save(Request $request): JsonResponse
                     ->first();
 
                 if ($existing) {
-                    // 계정과목 + 적요/예금주명 업데이트 (balance는 키값이므로 제외)
-                    $existing->update([
-                        'summary' => $data['summary'],
-                        'cast' => $data['cast'],
-                        'trans_office' => $data['trans_office'],
-                        'account_code' => $data['account_code'],
-                        'account_name' => $data['account_name'],
-                    ]);
+                    // Query Builder 사용: Eloquent의 decimal:2 cast가 balance를
+                    // dirty로 잘못 감지하여 unique 제약조건 위반을 일으키는 문제 방지
+                    DB::table('barobill_bank_transactions')
+                        ->where('id', $existing->id)
+                        ->update([
+                            'summary' => $data['summary'],
+                            'cast' => $data['cast'],
+                            'trans_office' => $data['trans_office'],
+                            'account_code' => $data['account_code'],
+                            'account_name' => $data['account_name'],
+                            'updated_at' => now(),
+                        ]);
                     $updated++;
                 } else {
                     BankTransaction::create($data);