diff --git a/lib/Manager.php b/lib/Manager.php
index 0d611c7..9dbd9f9 100644
--- a/lib/Manager.php
+++ b/lib/Manager.php
@@ -608,13 +608,11 @@ class Manager {
             throw new InvalidArgumentException("Service '{$service->identifier()}' is not capable of creating collections");
         }
         // convert properties if necessary
-        if (is_array($properties)) {
-            $collection = $service->collectionFresh()->getProperties()->jsonDeserialize($properties);
-        } else {
-            $collection = $properties;
+        if ($properties instanceof CollectionPropertiesMutableInterface === false) {
+            $properties = $service->collectionFresh()->getProperties()->jsonDeserialize($properties);
         }
         // Create collection
-        return $service->collectionCreate($target, $collection, $options);
+        return $service->collectionCreate($target, $properties, $options);
     }
 
     /**
@@ -642,13 +640,11 @@ class Manager {
             throw new InvalidArgumentException("Service '{$service->identifier()}' is not capable of updating collections");
         }
         // convert properties if necessary
-        if (is_array($properties)) {
-            $mutation = $service->collectionFresh()->getProperties()->jsonDeserialize($properties);
-        } else {
-            $mutation = $properties;
+        if ($properties instanceof CollectionPropertiesMutableInterface === false) {
+            $properties = $service->collectionFresh()->getProperties()->jsonDeserialize($properties);
         }
         // Update collection
-        return $service->collectionUpdate($target, $mutation);
+        return $service->collectionUpdate($target, $properties);
     }
 
     /**
diff --git a/src/stores/collectionsStore.ts b/src/stores/collectionsStore.ts
index 3223983..99855d1 100644
--- a/src/stores/collectionsStore.ts
+++ b/src/stores/collectionsStore.ts
@@ -296,9 +296,10 @@ export const useCollectionsStore = defineStore('mailCollectionsStore', () => {
         properties: properties.toJson()
       })
       
-      // Merge created collection into state
-      _collections.value[response.identifier] = response
-      indexCollection(response)
+      if (response instanceof CollectionObject) {
+        _collections.value[response.identifier] = response
+        indexCollection(response)
+      }
       
       console.debug('[Mail Manager][Store] - Successfully created collection:', response.identifier)
       return response
@@ -326,12 +327,14 @@ export const useCollectionsStore = defineStore('mailCollectionsStore', () => {
         properties: properties.toJson()
       })
       
-      if (_collections.value[response.identifier]) {
-        deindexCollection(_collections.value[response.identifier])
+      if (_collections.value[target]) {
+        deindexCollection(_collections.value[target])
       }
 
-      _collections.value[response.identifier] = response
-      indexCollection(response)
+      if (response instanceof CollectionObject) {
+        _collections.value[response.identifier] = response
+        indexCollection(response)
+      }
       
       console.debug('[Mail Manager][Store] - Successfully updated collection:', response.identifier)
       return response