diff --git a/database/entities/Object.ts b/database/entities/Object.ts
index 5fed8be3..9e176f31 100644
--- a/database/entities/Object.ts
+++ b/database/entities/Object.ts
@@ -28,7 +28,7 @@ export const createFromObject = async (object: LysandObjectType) => {
     return await client.lysandObject.create({
         data: {
             authorId: author?.id,
-            created_at: new Date(object.created_at),
+            created_at: new Date(object.created_at).toISOString(),
             extensions: object.extensions || {},
             remote_id: object.id,
             type: object.type,
diff --git a/server/api/oauth/token/index.ts b/server/api/oauth/token/index.ts
index 43302c06..e0abbaeb 100644
--- a/server/api/oauth/token/index.ts
+++ b/server/api/oauth/token/index.ts
@@ -58,6 +58,6 @@ export default apiRoute<{
         access_token: token.access_token,
         token_type: token.token_type,
         scope: token.scope,
-        created_at: token.created_at,
+        created_at: new Date(token.created_at).toISOString(),
     });
 });