diff --git a/packages/backend/src/server/api/endpoints/i/move.ts b/packages/backend/src/server/api/endpoints/i/move.ts
index 08d7368cd..423533692 100644
--- a/packages/backend/src/server/api/endpoints/i/move.ts
+++ b/packages/backend/src/server/api/endpoints/i/move.ts
@@ -5,6 +5,7 @@ import DeliverManager from '@/remote/activitypub/deliver-manager.js';
 import { deliver } from '@/queue/index.js';
 import { renderActivity } from '@/remote/activitypub/renderer/index.js';
 import type { IActivity } from '@/remote/activitypub/type.js';
+import { genId } from '@/misc/gen-id.js';
 import define from '../../define.js';
 import { ApiError } from '../../error.js';
 import { apiLogger } from '../../logger.js';
@@ -54,7 +55,7 @@ export const paramDef = {
 
 function moveActivity(to: User, from: User) {
 	const activity = {
-		id: 'foo',
+		id: genId(),
 		actor: from,
 		type: 'Move',
 		object: from,