Author of fastecdsa says there's no support for Windows[1]. So assuming you've tried all suggestion on GitHub issuge page[2], your choice is limited to ether using WSL or use Linux distro directly.


That might solve OP problem. Although i have doubt since looking at it's GitHub[3], i don't find any indication of source code change.

[1] https://github.com/AntonKueltz/fastecdsa/issues/39#issuecomment-537092428
[2] https://github.com/AntonKueltz/fastecdsa/issues/11
[3] https://github.com/ShadowJonathan/fastecdsa-any