diff --git a/src/WMS.Web.Repositories/BoxRepositories.cs b/src/WMS.Web.Repositories/BoxRepositories.cs
index 56c83ac8..b355a921 100644
--- a/src/WMS.Web.Repositories/BoxRepositories.cs
+++ b/src/WMS.Web.Repositories/BoxRepositories.cs
@@ -57,7 +57,7 @@ namespace WMS.Web.Repositories
         /// <returns></returns>
         public async Task<List<BoxResponse>> GetBox(List<string> BoxBillNos)
         {
-            BoxBillNos.ForEach(f => f.ToLower());
+            BoxBillNos = BoxBillNos.ConvertAll(d => d.ToLower());
             var list = await _context.Box.Include(x => x.Details).Where(f => BoxBillNos.Contains(f.BoxBillNo.ToLower())).ToListAsync();
             var resList = _mapper.Map<List<BoxResponse>>(list);