diff --git a/IRaCIS.Core.Application/Service/Visit/SubjectVisitService.cs b/IRaCIS.Core.Application/Service/Visit/SubjectVisitService.cs
index 5bdac402f..6c405f19f 100644
--- a/IRaCIS.Core.Application/Service/Visit/SubjectVisitService.cs
+++ b/IRaCIS.Core.Application/Service/Visit/SubjectVisitService.cs
@@ -607,7 +607,7 @@ namespace IRaCIS.Core.Application.Services
                                 item.InstanceInfoList.ForEach(x =>
                                 {
 
-                                    var keyFramesList = rowInfoList.Where(y => y.InstanceId == x.Id && y.NumberOfFrames != 0).Select(y => y.NumberOfFrames).Distinct().ToList();
+                                    var keyFramesList = rowInfoList.Where(y => y.InstanceId == x.Id && y.NumberOfFrames != 0&&y.NumberOfFrames!=null).Select(y => y.NumberOfFrames).Distinct().ToList();
 
                                     if (keyFramesList.Count() > 0)
                                     {