Better Private Key Management getting problems

[mazhar11-cou]

undefined
undefined
TypeError: Cannot read properties of undefined (reading 'toHexString')
    at isHexable (C:\Users\Mazhar\Documents\hardhat\ether-simple-storage\node_modules\@ethersproject\bytes\lib\index.js:9:21)
    at hexlify (C:\Users\Mazhar\Documents\hardhat\ether-simple-storage\node_modules\@ethersproject\bytes\lib\index.js:175:9)
    at new SigningKey (C:\Users\Mazhar\Documents\hardhat\ether-simple-storage\node_modules\@ethersproject\signing-key\lib\index.js:20:82)
    at new Wallet (C:\Users\Mazhar\Documents\hardhat\ether-simple-storage\node_modules\@ethersproject\wallet\lib\index.js:120:36)
    at main (C:\Users\Mazhar\Documents\hardhat\ether-simple-storage\encryptKey.js:8:20)
    at Object.<anonymous> (C:\Users\Mazhar\Documents\hardhat\ether-simple-storage\encryptKey.js:17:1)
    at Module._compile (node:internal/modules/cjs/loader:1105:14)
    at Object.Module._extensions..js (node:internal/modules/cjs/loader:1159:10)
    at Module.load (node:internal/modules/cjs/loader:981:32)
    at Function.Module._load (node:internal/modules/cjs/loader:822:12) ```

I don't understand what my problems when i put ``encryptedKey.js`` command. Please help me. 

[eli5mecoding]

Can you post your entire encryptKey.js & .env code so we can check?