3652745 - "Unknown error while connecting to external" Error in External Hook Logs

After implementing an external hook, you can see the following error when saving or changing an object instance:

• FAILED_PRECONDITION: Error: Unknown error while connecting to external pre-hook for XYZ. Please contact your administrator with log ID 00000000-0000-0000-0000-000000000000.
• FAILED_PRECONDITION: Error: Unknown error while connecting to external post-hook for XYZ. Please contact your administrator with log ID 00000000-0000-0000-0000-000000000000.

When accessing the Logs into the Extensibility Administration, you can see the following error:

• Error raised from the connector service: A network error occurred while making a call to the external system.

• SAP Sales Cloud Version 2
• SAP Service Cloud Version 2

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