diff --git a/packages/backend/src/core/QueueService.ts b/packages/backend/src/core/QueueService.ts
index 48ff00c8cef8bce51a02dd894e0f7370988ab82b..e1da0516d1d57ef418f289d7e9bc6b4af55c183d 100644
--- a/packages/backend/src/core/QueueService.ts
+++ b/packages/backend/src/core/QueueService.ts
@@ -97,6 +97,8 @@ export class QueueService {
 	 */
 	@bindThis
 	public async deliverMany(user: ThinUser, content: IActivity | null, inboxes: Map<string, boolean>) {
+		if (content == null) return null;
+
 		const opts = {
 			attempts: this.config.deliverJobMaxAttempts ?? 12,
 			backoff: {