Loop Over Items does not loop through all items (Firebase → Notion)

[ThiTou]

Describe the problem/error/question

I am building a very simple workflow that should sync data from Firebase to a Notion database.

1. A Firebase node retrieves a list of agents.

2. A “flatten” Code node converts the result into a list of items like this:

json

[ { "agentName": "Agent A (Group)", "agentRef": "id_001", "lastSync": "2025-12-05T15:26:48.626146Z", "nbCompanies": 2 }, { "agentName": "Agent B (Group)", "agentRef": "id_002", "lastSync": "2025-09-22T10:08:44.238688Z", "nbCompanies": 4 }, { "agentName": "Agent C (Group)", "agentRef": "id_003", "lastSync": "2024-12-14T14:37:27.784322Z", "nbCompanies": 18 } // etc. (9 items in total)]

3. The Loop Over Items (Split in Batches) node receives all 9 items as input.

4. For each item, I do:

   • Notion - Query on a “Id” field where**{{$json.agentRef}}matches**

   • IF - Exists?

     • true → Notion - Update Page

     • false → Notion - Create Page

Goal: for each item in the list, create or update a Notion page with the agentName, agentRef, lastSync, and nbCompanies properties.​

Problem

The Loop Over Items node does not process all items passed to it.

In the logs:

• The node right before the Loop shows 9 items.

• The Loop starts, but only the first page is updated in Notion, then the execution finishes as if everything were done (no error).​

What I have already checked

• The “flatten” Code node really returns 9 separate items (not a single item containing an array).​

• In the Loop, the batch size is set to 1 and the “loop” connection goes back into the Loop Over Items node.​

• The Notion nodes work correctly when tested with a single item.​

Questions

1. Am I using the Loop Over Items (Split in Batches) node correctly in this scenario?

2. What could cause the loop to stop before processing all 9 items when there is no error in the execution?

What is the error message (if any)?

None

Please share your workflow

Share the output returned by the last node

Information on your n8n setup

• n8n version: 2.0.3
• Database (default: SQLite):d default
• n8n EXECUTIONS_PROCESS setting (default: own, main): Default
• Running n8n via (Docker, npm, n8n cloud, desktop app): Hostinger
• Operating system: VPS

[Wouter_Nigrini]

Hi @ThiTou,

Why do you have two Loop nodes? You’re essentially creating a nested loop which can cause confusion and issues if the data is simple enough.

However, in your second loop node, rather set the batch to 1 so you loop over 1 item at a time.

For example this flow will serve you better as you can see the loop iterated over each item of the 3 items in the example trying to find one item at a time to compare, update or create

[ThiTou]

Indeed. It makes a lot more sense to me know.
I didn’t mean to keep the double loop in the workflow though .
I tried to loop over agents and then for each agent loop over the companies listed in each agent collection originally but I stripped it down as the double loop created issues.

Thanks @Wouter_Nigrini !

[Wouter_Nigrini]

That is great news! Shout if you need any further help