Node Red Authentication PW Hash issue

Dears I'm new in the forum and I came across this post. Actually what described has happened to me too. What I tryed more is to run more times for the same password: with my surprise, every time hash -pw generates a different hash. There's no way to change this even if node-red is stopped.Cattura
Any suggestion?
When I try node -e "console.log(require('bcryptjs').hashSync(process.argv[1], 8));" your-password-here I got this
`module.js:549
throw err;
^

Error: Cannot find module 'bcryptjs'
at Function.Module._resolveFilename (module.js:547:15)
at Function.Module._load (module.js:474:25)
at Module.require (module.js:596:17)
at require (internal/module.js:11:18)
at [eval]:1:13
at ContextifyScript.Script.runInThisContext (vm.js:50:33)
at Object.runInThisContext (vm.js:139:38)
at Object. ([eval]-wrapper:6:22)
at Module._compile (module.js:652:30)
at evalScript (bootstrap_node.js:463:27)
`
Thanks in advance