SwaggerHub error 500 during update API definitions

I tried to update my API's  swagger definition on mock server. For test i download swagger file from https://petstore.swagger.io/v2/swagger.json. And try to send POST request to swaggerhub.com/apis/was_mock/uber_private.

Where {owner} = was_mock  and {api} = uber_private.

Also  i added to header "Authorization" and my secret key. File attached as "form-data" with name "definition".

When i send request - I received folowing exception 

{
    "code": 500,
    "message": "There was an error processing your request. It has been logged (ID: 25c6ad4735c99ccd)"
}