Cannot deploy: Command failed with exit code 127: CI = npm run build

Hello there, I am unable to deploy my website which is developed using React, javascript, CSS and HTML.

4:22:44 PM: $ CI = npm run build
4:22:44 PM: bash: CI: command not found
4:22:44 PM: ​
4:22:44 PM: ────────────────────────────────────────────────────────────────
4:22:44 PM: “build.command” failed
4:22:44 PM: ────────────────────────────────────────────────────────────────
4:22:44 PM: ​
4:22:44 PM: Error message
4:22:44 PM: Command failed with exit code 127: CI = npm run build (Search results for '"non-zero exit code: 127"' - Netlify Support Forums)
4:22:44 PM: ​
4:22:44 PM: Error location
4:22:44 PM: In Build command from Netlify app:
4:22:44 PM: CI = npm run build
4:22:44 PM: ​
4:22:44 PM: Resolved config
4:22:44 PM: build:
4:22:44 PM: command: CI = npm run build
4:22:44 PM: commandOrigin: ui
4:22:44 PM: publish: /opt/build/repo/build
4:22:44 PM: publishOrigin: ui
4:22:44 PM: Caching artifacts
4:22:44 PM: Started saving node modules
4:22:45 PM: Finished saving node modules
4:22:45 PM: Started saving build plugins
4:22:45 PM: Finished saving build plugins
4:22:45 PM: Started saving pip cache
4:22:45 PM: Finished saving pip cache
4:22:45 PM: Started saving emacs cask dependencies
4:22:45 PM: Finished saving emacs cask dependencies
4:22:45 PM: Started saving maven dependencies
4:22:45 PM: Finished saving maven dependencies
4:22:45 PM: Started saving boot dependencies
4:22:45 PM: Finished saving boot dependencies
4:22:45 PM: Started saving rust rustup cache
4:22:45 PM: Finished saving rust rustup cache
4:22:45 PM: Started saving go dependencies
4:22:45 PM: Finished saving go dependencies
4:22:48 PM: Build failed due to a user error: Build script returned non-zero exit code: 2
4:22:48 PM: Creating deploy upload records
4:22:48 PM: Failing build: Failed to build site
4:22:48 PM: Failed during stage ‘building site’: Build script returned non-zero exit code: 2 (Search results for '"non-zero exit code: 2"' - Netlify Support Forums)
4:22:48 PM: Finished processing build request in 46.741393441s

The build command is CI= npm run build and not CI = npm run build. You added an extra space.