build.command failed when deploying next app to netlify

Job ID: 34749531

Budget: $10 – $30 USD

I've build a nextjs Web app with Sanity as headless cms.
As I am finished now i tried to deploy it to vercel first but got some errors. Removed most of them. But failed to deploy it. After it i tried to deploy on netlify but also rejeted with a build.command failed error. Can not figure out how to fix this. CI = false also does not work.
Related categories: JavaScript HTML Node.js React.js CI/CD