Undefined set variable inside loop after first item

[MutedJam]

Hi @Andrelfc, welcome to the community!

The problem here will be that your PostLogin node returns 1 item, but your GetWorkflowById node receives multiple items. So, you probably want to use an expression like {{ $("PostLogin").first().json["headers"]["set-cookie"] }} to make sure to always reference the first (and only) item from your PostLogin node.

You might want to check out this post for a slightly longer explanation:

HTTP node misses the JSON payload for 2nd iteration

Hi @physx911, seeing you have more than one item on your HTTP Request node but only one item on the clean data node you’re referencing in your expression will lead to the following behaviour: For the first item arriving on the HTTP Request node, n8n will look up the first item on the clean data node which works fine For the second item arriving on the HTTP Request node, n8n will look up the second item on the clean data node which doesn’t exist So, what you most likely want here is have n8n a…

Let me know if you have any questions on this