Just noticed that the ‘Set Contact Attributes’ block in my Architect flow returns a 400 error when trying to push a Zendesk ticket ID into a custom attribute named ext_zd_ticket_id.
The flow is deployed in the eu-west-1 region, and the attribute exists in the tenant. Am I hitting a naming convention limit or a permissions issue with the IVR user profile?
Ah, this is a recognized issue…
The 400 error usually stems from the JSON structure sent to the Set Contact Attributes action. When pushing external IDs like Zendesk tickets, the payload must explicitly define the type as string or integer depending on your schema definition. If the type is missing, the API rejects the request. Try using this exact JSON format in the action configuration:
{
"attributes": {
"ext_zd_ticket_id": {
"value": "{{contact.interaction.attributes.zendesk_ticket_id}}",
"type": "string"
}
}
}
Ensure the variable {{contact.interaction.attributes.zendesk_ticket_id}} actually contains data before reaching this block. If it is null, the API might throw a validation error. You can add a Data Action before the Set Contact Attributes block to log the value and verify it is not empty.
In my experience with legal discovery exports, clean metadata mapping at the IVR level is critical. If the ext_zd_ticket_id is not correctly attached to the contact object during the interaction, it will not appear in the final bulk export JSON payloads. This makes tracing digital channel transcripts back to the original support ticket nearly impossible for audit trails. I recommend verifying the attribute exists in the Contact Attributes configuration under Admin > Contact Attributes. If it is missing there, create it with the exact name ext_zd_ticket_id and ensure it is set as a custom attribute. Also, check that the IVR user profile has write permissions for contact attributes. Sometimes, even if the attribute exists, the user profile lacks the specific permission to update it during the flow execution.
Ah, yeah, this is a known issue…
The 400 error often happens when the attribute type in the payload does not match the schema. Ensure ext_zd_ticket_id is explicitly defined as string in the JSON object.
I verified this in JMeter with 50 concurrent sessions. The fix worked immediately after adding the type field.