Trying to upload site to netlify, "build.command failed"

This is not the proper way to open a support ticket.

When you first joined this forum there was a big pink banner at the very top:

In case you dismissed it -as it looks like- let me remind you that you need to share more than a generic description, like the source code of the project for people to see what is going on.

The Requesting Help guidelines of the aforementioned banner are meant to be read before asking for help in the forum.