SLack Send message send 2 messages why?

[scal]

Describe the problem/error/question

When I send a confirmation slack message at the end of my workflow, I can see from execution tab that there is one single execution but my slack node send 2 message
Here is below the workflow screen shot where last node execution is in red square

In my slack chanel I receive the following :

The first message is from the output, but the second message why it is send ?

Thanks for help

Share the output returned by the last node

[
{
“ok”: true,
“channel”: “C0AFGAMF6SF”,
“message”: {
“user”: “U0AG1HN4UPK”,
“type”: “message”,
“ts”: “1772101020.346269”,
“bot_id”: “B0AFLJB3LKY”,
“app_id”: “A0AFNL4D20J”,
“text”: “ Thanks <@U0AFG86US0K>! Your support request has been created \n_Automated with this <http://localhost:5678/workflow/jHAhoSJX2temlwyqAejRB?utm_source=n8n-internal&amp;utm_medium=powered_by&amp;utm_campaign=n8n-nodes-base.slack_3dba50fea55b8a965fa42dc5ff83445861607f63463e6fd81c2553d59ecfeac2|n8n workflow>",
“team”: “T0AG1H6D5DX”,
“bot_profile”: {
“id”: “B0AFLJB3LKY”,
“app_id”: “A0AFNL4D20J”,
“user_id”: “U0AG1HN4UPK”,
“name”: “n8n”,
}
]

Information on your n8n setup

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

[BramKn]

You have 2 items going into the slack node so it will run for both items.
You will need to aggregate them, limit them or set the slack node to run only once.

[Mayank1024]

Hey @scal,
Welcome to the community,

n8n sends one Slack message per item it receives at the Slack node. As the execution shows as a single run, the node before Slack is passing 2 items, so Slack ended up posting twice.

it must have been added by mistake, remove the additional item and the problem would be solved

Let me know if it helped.

[jitesh]

Hey @scal welcome to the community!

You’re getting 2 messages because there are 2 items sent as an input to the Slack node.

If your 2nd item is always blank, you may use the ‘Limit’ node to limit to the 1st item only.

hope this helps.

[scal]

The reason of the 2 items I guess was due to the merge node I have place to poulate some previous data.

I remove the merge node and my previous data from previous node directly and it works ok now

Thanks