diff --git a/server/helpers/custom-validators/activitypub/activity.ts b/server/helpers/custom-validators/activitypub/activity.ts
index 69558e358..b5c96f6e7 100644
--- a/server/helpers/custom-validators/activitypub/activity.ts
+++ b/server/helpers/custom-validators/activitypub/activity.ts
@@ -49,7 +49,7 @@ function isActivityValid (activity: any) {
 }
 
 function isFlagActivityValid (activity: any) {
-  return isBaseActivityValid(activity.type, 'Flag') &&
+  return isBaseActivityValid(activity, 'Flag') &&
     isAbuseReasonValid(activity.content) &&
     isActivityPubUrlValid(activity.object)
 }