Internal Server Error when using custom extraction model

Question

I trained multiple custom extraction models of different kind and when I try to call one to analyse a test document I receive an InternalServerError. When I swap the model - input data remains the same - it works. I tested the model via browser and it works like a charm. So what is the problem here?

Unable to retrieve continuation token: cannot serialize '_io.BufferedReader' object
Traceback (most recent call last):
  File "C:\...\document_intelligence\venv\lib\site-packages\azure\core\polling\base_polling.py", line 757, in run
    self._poll()
  File "C:\...\document_intelligence\venv\lib\site-packages\azure\core\polling\base_polling.py", line 789, in _poll
    raise OperationFailed("Operation failed or canceled")
azure.core.polling.base_polling.OperationFailed: Operation failed or canceled

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "C:\...\document_intelligence\main.py", line 32, in <module>
    results = poller.result()
  File "C:\...\document_intelligence\venv\lib\site-packages\azure\core\polling\_poller.py", line 251, in result
    self.wait(timeout)
  File "C:\...\document_intelligence\venv\lib\site-packages\azure\core\tracing\decorator.py", line 78, in wrapper_use_tracer
    return func(*args, **kwargs)
  File "C:\...\document_intelligence\venv\lib\site-packages\azure\core\polling\_poller.py", line 270, in wait
    raise self._exception  # type: ignore
  File "C:\...\document_intelligence\venv\lib\site-packages\azure\core\polling\_poller.py", line 185, in _start
    self._polling_method.run()
  File "C:\...\document_intelligence\venv\lib\site-packages\azure\core\polling\base_polling.py", line 772, in run
    raise HttpResponseError(response=self._pipeline_response.http_response, error=err) from err
azure.core.exceptions.HttpResponseError: (InternalServerError) An unexpected error occurred.
Code: InternalServerError
Message: An unexpected error occurred.
Exception Details:	(InternalServerError) An unexpected error occurred.
	Code: InternalServerError
	Message: An unexpected error occurred.

Answer 1

After retraining the model with a few additional documents the error vanished. It appears to have been a hickup of some sort.