Can you please share the definition of your stored procedure? Basically the exception you are seeing can be caused by either one of the following:
1. The result set contains fields that are not supported by our converters. (This should not be the case as initially you are able to read it).
2. The reading of the result times out due to a problem with the server.
I tried executing the same workflow on my side and it seems that everything is working as expected.
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