Upload DWG or DXF file in M-Files using C#

As far as M-Files is concerned the actual data type of the document should be largely irrelevant; M-Files simply deals with it as a set of binary data.  I haven't heard of others who have had similar issues.

Have you looked at the actual resulting HTTP requests using a HTTP debugging proxy to see what's being sent over the wire, and to see whether it's different between PDF and the ones that you are having an issue with?

I don't use HTTP debugging yet.
Just check with POSTMAN, its working fine.
but in C# upload only PDF is correct other formats are corrupted.

If it works fine in Postman then there are no issues with the REST API, but there's obviously a difference in the resulting HTTP request in C# vs Postman.

A HTTP debugging proxy would be my next step.  If you have it working in Postman then it's a matter of playing spot-the-difference between the working request in Postman and the non-working request in C#.  Once you know that core issue you can look at what you might need to change in the C# application.

If it works fine in Postman then there are no issues with the REST API, but there's obviously a difference in the resulting HTTP request in C# vs Postman.

A HTTP debugging proxy would be my next step.  If you have it working in Postman then it's a matter of playing spot-the-difference between the working request in Postman and the non-working request in C#.  Once you know that core issue you can look at what you might need to change in the C# application.