What causes "error-unserved-rooms-cannot-be-placed-onhold" in RocketChat/Rocket.Chat?

Only expose Hold for rooms with an active servedBy; gate the UI on room.servedBy being truthy.

RocketChat/Rocket.Chat · error · Error

error-unserved-rooms-cannot-be-placed-onhold

Error message

error-unserved-rooms-cannot-be-placed-onhold

What it means

Thrown by placeRoomOnHold when `room.servedBy` is falsy. A chat without a serving agent cannot be put on hold because there is no agent relationship to suspend. This is the last guard before the room/subscription update.

Source

Thrown at apps/meteor/ee/server/local-services/omnichannel.internalService.ts:57

		if (!room || !isOmnichannelRoom(room)) {
			throw new Error('error-invalid-room');
		}
		if (!room.open) {
			throw new Error('error-room-already-closed');
		}
		if (room.onHold) {
			throw new Error('error-room-is-already-on-hold');
		}
		const restrictedOnHold = settings.get('Livechat_allow_manual_on_hold_upon_agent_engagement_only');
		const canRoomBePlacedOnHold = !room.onHold;
		const canAgentPlaceOnHold = !room.lastMessage?.token;
		const canPlaceChatOnHold = canRoomBePlacedOnHold && (!restrictedOnHold || canAgentPlaceOnHold);
		if (!canPlaceChatOnHold) {
			throw new Error('error-cannot-place-chat-on-hold');
		}
		if (!room.servedBy) {
			throw new Error('error-unserved-rooms-cannot-be-placed-onhold');
		}

		const [roomResult, subsResult] = await Promise.all([
			LivechatRooms.setOnHoldByRoomId(roomId),
			Subscriptions.setOnHoldByRoomId(roomId),
			Message.saveSystemMessage<IOmnichannelSystemMessage>('omnichannel_placed_chat_on_hold', roomId, '', onHoldBy, { comment }),
		]);

		if (roomResult.modifiedCount) {
			void notifyOnRoomChangedById(roomId);
		}

		if (subsResult.modifiedCount) {
			void notifyOnSubscriptionChangedByRoomId(roomId);
		}

		await callbacks.run('livechat:afterOnHold', room);
	}

View on GitHub (pinned to f9d3ec372b)

Solutions

Only expose Hold for rooms with an active servedBy; gate the UI on room.servedBy being truthy.
Re-fetch the room to confirm it is still assigned before calling placeRoomOnHold.
If the chat is queued, route it through the assignment flow first, not the hold flow.

Example fix

// before
await omnichannelService.placeRoomOnHold(room, comment, user);

// after
if (!room.servedBy) {
  throw new Error('Room has no serving agent; cannot place on hold');
}
await omnichannelService.placeRoomOnHold(room, comment, user);

Defensive patterns

Strategy: validation

Validate before calling

if (!room.servedBy) {
  throw new Error('Room has no serving agent; cannot place on hold');
}
await omnichannelService.placeRoomOnHold(room, comment, user);

Type guard

function hasServingAgent(room: unknown): boolean {
  return !!room && !!(room as any).servedBy;
}

Try / catch

try {
  await omnichannelService.placeRoomOnHold(room, comment, user);
} catch (e) {
  if (e instanceof Error && e.message === 'error-unserved-rooms-cannot-be-placed-onhold') {
    notifyUser('This chat has no assigned agent.');
    return;
  }
  throw e;
}

Prevention

Only show Hold for rooms with an active servedBy.
Re-fetch the room to confirm assignment before the call.
Route unassigned chats through assignment, not hold.

When it happens

Trigger: Calling placeRoomOnHold on a room whose servedBy field is null/undefined: an unclaimed queued inquiry, a room whose agent was removed, or a chat returned to the queue.

Common situations: Trying to hold a chat that is still queued (no agent assigned); the servedBy relation was cleared by a transfer/abandon flow before the hold call.

Related errors

AI-assisted analysis of RocketChat/Rocket.Chat@f9d3ec372b (2026-08-12). Data as JSON: /api/errors/c5d83dfa77dc76ac. Report an issue: GitHub.