N8N error (Cant determine which item to use)

I dont know why often this kind of error has been happening with my clients account.

I need some assistence due to a lot of trouble it has been causing.

Can anyone tell me how I fix it? Or, in the next N8N update release will it be resolved?

Hi, are you using a merge node in that workflow? Could you please provide a clear screenshot of your workflow or directly share the workflow JSON here?



Try to config this merge option to “combine”

“Append” waits for all your previous nodes/wires to exist, which is why you got that error


Right here?

Yes and choose Combine then “All Possible Combination”



Nothing is coming from the merge. What should I do?

If you pin the data, try to click play again from the webhook node


then trigger on this node


Same result.

No different.

Its coming empty.

What about this option? it just create/insert data on supabase before merge node right?



I tried it again but failed.

What should I do?

I have several workflows with complex merges, but this will depend on the output of the previous nodes. If I test it with just Set nodes, each having only one parameter output, it can run and take data from the initial node without a merge node.


This is your case

Got it. Thanks.



Now I having this problem.

If there’s a node that’s cutting off your workflow’s path, you can try bypassing it directly to the error node using a Merge node. It would be too complex for me to ask about the parameter types of all the nodes in your previous workflow.

Are you using a session system to adapt to different workflow concepts? If so, try connecting it with Typebot. It would be very useful for streamlining your session handling in a chat context.

It is a bug. @tridi

But, it is strange.

It is the underlined variable.


I copied to editor and ran it mannually. It worked.