diff --git a/src/Http/Controllers/AttachController.php b/src/Http/Controllers/AttachController.php
index 037c13f..124534c 100644
--- a/src/Http/Controllers/AttachController.php
+++ b/src/Http/Controllers/AttachController.php
@@ -43,7 +43,7 @@ public function getAvailableResources($request, $relationship)
 
         $query = $field->resourceClass::newModel();
 
-        return forward_static_call($this->associatableQueryCallable($request, $query), $request, $query)->get()
+        return (forward_static_call($this->associatableQueryCallable($request, $query), $request, $query) ?? $query)->get()
             ->mapInto($field->resourceClass)
             ->filter(function ($resource) use ($request, $field) {
                 return $request->newResource()->authorizedToAttach($request, $resource->resource);