3730807 - Search Service Exception AI Natural Language Search is currently unavailable: Joule error

Joule has been integrated with a supported product. However Joule's conversational user interface fails with the error:
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Search Service Exception 
AI Natural Language Search is currently unavailable
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Screenshot:

• Joule AI copilot
• SAP S/4HANA Cloud Public Edition
• SAP Business Technology Platform (SAP BTP. URL: https://cockpit.btp.cloud.sap) 
• SAP Cloud Foundry (CF)

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