Compile error with generated c# code for .net

Hello,

I imported an open Api specification into my workspace and so I got thiese API definition:

https://app.swaggerhub.com/apis/FHuber/EvoBilliingApi/v1

Wenn I use the CodeGen and export csharp code, using no public api and as target framework .net standards 1.3, because I wan to generate a

c# class library with .net core, running on linux docker containers.

When I try to compile these source, I got an error at cöass ApiClient.cs, in method PrepareRequest:

Unable to convert "System.Action<System.IO.Stream>" to "byte[]".

Does anybody know what this means? I am no able to fix this bug, so I will set it under comments, because I am not using

this part of code in my APIs.

Kind regards,

Florian