Api works in Unity Editor, but doesn't work on build

[torontochen]

I am making a multiplayer game with Mirror, need to load several states for player with graph api.The local graphql URL is http://localhost:4000/graphql.It works smoothly in Unity Editor, but when I run a build locally as client , the api doesn't work.Even after I sign in build as host, it doesn't work either.I am not sure if i need modify the url when running on build.I tried many other ways, none works out.