Failed-to-publish-post.md

When I publish a post, I get a 422 status error. It seems to fail to request api.github.com/repos/rkaneko/weblog/git/tree?[some id].

• console log screenshot

• server response

{
  "message": "tree.path contains a malformed path component",
  "documentation_url": "https://developer.github.com/v3/git/trees/#create-a-tree"
}