NoSuchKey The specified key does not exist error happens when you enable the async mode and you try to access the output while the job is still working on your request.
To fix this error, please add a background job check in your code to see the job status. To manage background jobs, please use one of our code samples here
Or use the code sample with async here.
"async": true, the result will returns a
jobId. Please use this
jobId to check the job status using the
Background Jobs Check in the Postman collection.
For more information about background job check, please visit our API Docs