diff --git a/Src/Dlhis.Sys/DataPermission/Controllers/DataPermissionsController.cs b/Src/Dlhis.Sys/DataPermission/Controllers/DataPermissionsController.cs
index d8b42c60..6af302ce 100644
--- a/Src/Dlhis.Sys/DataPermission/Controllers/DataPermissionsController.cs
+++ b/Src/Dlhis.Sys/DataPermission/Controllers/DataPermissionsController.cs
@@ -33,7 +33,7 @@ public class DataPermissionsController : ControllerBase
     [HttpGet("assignments")]
     public async Task<List<Guid>> GetAssignmentsAsync(string assignValue, 
         [EnumDataType(typeof(DataPermissionAssignmentEnumType))] DataPermissionAssignmentEnumType uniqueType,
-        DeviceTypeEnumType type)
+        DeviceTypeEnumType? type)
     {
         return await _dataPermissionService.GetAssignmentsAsync(assignValue, uniqueType, type);
     }