diff --git a/Controllers/SubmissionController.cs b/Controllers/SubmissionController.cs
index c984d48..b2defa5 100644
--- a/Controllers/SubmissionController.cs
+++ b/Controllers/SubmissionController.cs
@@ -31,7 +31,7 @@ namespace _2021_backend.Controllers
             Submission sub = new Submission(aDto, ip);
             foreach (var tm in Context.Sessions)
             {
-                if (aDto.Timelist.Any(it => it.Day.Day == tm.Day.Day && it.BeginTime.TimeOfDay == tm.BeginTime.TimeOfDay))
+                if(aDto.Timelist != null)if (aDto.Timelist.Any(it => it.Day.Day == tm.Day.Day && it.BeginTime.TimeOfDay == tm.BeginTime.TimeOfDay))
                 {
                     sub.Timelist.Add(tm.Guid);
                 }