Build error SAP Web IDE

I want to build my UI5 App - yesterday it was working fine but today im getting the error:

Unhandled rejection Error: EACCES: permission denied, mkdir '/mnt/npm_cache/_cacache'

Please follow the relevant troubleshooting tips below:

ERROR: "Unable to find local grunt"- Right-click the project folder, select "Clean npm Folder", and build again.

ERROR: "npm ERR! code EINTERGITY"- Delete the "package-lock.json" file from the project and build again.

Im using grunt and babel for ES6:

package.json

"devDependencies": {
"babel-core": "7.0.0-alpha.19",
"babel-preset-env": "2.0.0-alpha.19",
"grunt-babel": "7.0.0",
"@sap/grunt-sapui5-bestpractice-build": "1.3.65"
}

i cleaned the npm folder and deleted package-lock.json but with no success.