Train request- Error 1002

Hello everybody,

i recently got access to the Microsoft Form Recognizer Preview. After setting up a Form Recognizer Ressource and a Blob Storage Container, i put together a train request according to the Quickstart Documentation. Dispatching my request always leads me to the Error Code 1002 like this:

`$ error":{"code":"1002","message":"Train request is either invalid or missing required parameters. Please reference the API reference and retry your request."}}`

I already added 5 documents of the same type to my Blob Storage and followed the steps of the Quickstart guide very precisely. After i repeated this process for a few times and always obtained the same result, i dont know what to do.

I would be very glad if someone could help me with this issue. Thank you in advance.

Cheers
puN1ka