Hi @Bas.T,
Thank you for providing the link to your configuration.
I discovered the problem: when executing the first transformer (HTTP Transformer), the previous payload is replaced with the response from the HTTP call. Therefore, when the second transformer is launched, the “payload” attribute is no longer present, preventing the iterate call from occurring.
To resolve this, you can move the first HTTP Transformer into the “Merge Transformer” so that the previous payload is not replaced and can be used in the next transformer.
Please find below for the explaination: Merger Transformer