Hi @rut7 ,
Reason is, In your delivery there will be syntax like <%= targetData.______ %> , This syntax in delivery will expect target data from input transition. if there is no such target data, then you will be getting this error.
<%= targetData.field123 %>

Solution:
If you use a workflow,
Search for those targetData in your delivery, and in your workflow, add it as additional data using enrichment.
Example, if you have script <%= targetData.field123 %> in delivery, create an enrichment before your delivery > add an output column as @field123


If you use SOAP API Request (transactional message), then modify target data <%= targetData._____ %> with syntax as below, (Depends on your Payload Request structure)

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