Freeze When i use this command npm run build && npm start command not working

[asepsisIT]

I have run this command = npm run build && npm start

But some how npm run build command not working for me.
Node version : v8.11.4
Npm version : 5.6.0

Freeze :

Compiled successfully.

┌ /
├ /_app
├ /_document
├ /_error
├ /active
├ /ask
├ /best
├ /bestcomments
├ /bookmarklet
├ /changepw
├ /dmca
├ /favorites
├ /forgot
├ /formatdoc
├ /front
├ /hidden
├ /item
├ /jobs
├ /leaders
├ /lists
├ /login
├ /newcomments
├ /newest
├ /newpoll
├ /newsfaq
├ /newsguidelines
├ /newswelcome
├ /noobcomments
├ /noobstories
├ /reply
├ /security
├ /show
├ /showhn
├ /shownew
├ /submit
├ /submitted
├ /threads
├ /upvoted
└ /user

[clintonwoo]

I've made a massive update to this project and haven't seen this issue occur. So I will close this issue but you can recreate if you still see it