Package not found

[Frangeris Peguero]

{
  "errorMessage": "Cannot find module 'js-yaml'",
  "errorType": "Error",
  "stackTrace": [
    "require (internal/module.js:20:19)",
    "Object.<anonymous> (/var/task/helpers/validate.js:1:76)",
    "Module._compile (module.js:570:32)",
    "Object.Module._extensions..js (module.js:579:10)",
    "Module.load (module.js:487:32)",
    "tryModuleLoad (module.js:446:12)",
    "Function.Module._load (module.js:438:3)"
  ]
}