diff --git a/src/Api/Controllers/CollectionsController.cs b/src/Api/Controllers/CollectionsController.cs
index 1bc8a60ab..dab97618b 100644
--- a/src/Api/Controllers/CollectionsController.cs
+++ b/src/Api/Controllers/CollectionsController.cs
@@ -92,7 +92,7 @@ namespace Bit.Api.Controllers
             }
 
             var collection = model.ToCollection(orgIdGuid);
-            await _collectionService.SaveAsync(collection, model?.GroupIds.Select(g => new Guid(g)));
+            await _collectionService.SaveAsync(collection, model.GroupIds?.Select(g => new Guid(g)));
             return new CollectionResponseModel(collection);
         }
 
@@ -106,7 +106,7 @@ namespace Bit.Api.Controllers
                 throw new NotFoundException();
             }
 
-            await _collectionService.SaveAsync(model.ToCollection(collection), model?.GroupIds.Select(g => new Guid(g)));
+            await _collectionService.SaveAsync(model.ToCollection(collection), model.GroupIds?.Select(g => new Guid(g)));
             return new CollectionResponseModel(collection);
         }
 
diff --git a/src/Core/Models/Api/Response/CollectionResponseModel.cs b/src/Core/Models/Api/Response/CollectionResponseModel.cs
index d1685a09e..e42d5d07a 100644
--- a/src/Core/Models/Api/Response/CollectionResponseModel.cs
+++ b/src/Core/Models/Api/Response/CollectionResponseModel.cs
@@ -40,13 +40,13 @@ namespace Bit.Core.Models.Api
 
     public class CollectionDetailsResponseModel : CollectionResponseModel
     {
-        public CollectionDetailsResponseModel(Collection collection, IEnumerable<Guid> collectionIds)
+        public CollectionDetailsResponseModel(Collection collection, IEnumerable<Guid> groupIds)
             : base(collection, "collectionDetails")
         {
-            CollectionIds = collectionIds;
+            GroupIds = groupIds;
         }
 
-        public IEnumerable<Guid> CollectionIds { get; set; }
+        public IEnumerable<Guid> GroupIds { get; set; }
     }
 
     public class CollectionUserDetailsResponseModel : CollectionResponseModel