Error: HDPrivateKey

[elvis-hp]

const bitcoreCash = require('bitcore-lib-cash');
...
const xpriv = code.toHDPrivateKey();
const hdPrivateKey = new bitcoreCash.HDPrivateKey(xpriv); //-> error here ...

I have an error when I call the HDPrivateKey function, can you help me fix it?
Uncaught AssertionError {name: "AssertionError", actual: false, expected: true, operator: "==", message: "parentFingerPrint argument is not a buffer", …}