I am using AES Excryption for encypting my data while making post request

const data = {
          orgId: 13 ,
          userId: 123456 ,
          appId: 9505,
          screenId: '1,2,3,4,5,6',
      };

const secret="abcdefgh";



try {
    const response = await axios.post("/getTokens.do?method=getScreenTokens", {data: encryptedData});
    console.log('Response:', response.data);
    } catch (error) {
      console.error('Error sending data:', error);
    }

 function encrypt(plaintext, secret) {
      var key = CryptoJS.enc.Utf8.parse(secret);
      let iv = CryptoJS.lib.WordArray.create(key.words.slice(0, 4));
      setIV(iv);
      console.log("IV : " + CryptoJS.enc.Base64.stringify(iv));
      
      // Encrypt the plaintext
      var cipherText = CryptoJS.AES.encrypt(plaintext, key, {
          iv: iv,
          mode: CryptoJS.mode.CBC,
          padding: CryptoJS.pad.Pkcs7
      });
      return cipherText.toString();
  }

  function decrypt(ciphertext, secret) {
    var key = CryptoJS.enc.Utf8.parse(secret);
    let iv = CryptoJS.lib.WordArray.create(key.words.slice(0, 4));

    // Decrypt the ciphertext
    var decrypted = CryptoJS.AES.decrypt(ciphertext, key, {
        iv: iv,
        mode: CryptoJS.mode.CBC,
        padding: CryptoJS.pad.Pkcs7
    });

    const decryptedText = decrypted.toString(CryptoJS.enc.Utf8);

    // Check if decryption was successful
    if (!decryptedText) {
        throw new Error("Decryption failed. Malformed UTF-8 data.");
    }

    return decryptedText;
}


const encryptedData = encrypt(JSON.stringify(data), secret);
console.log("EncodedPayload ->",encryptedData)
      
const base64CipherText = CryptoJS.enc.Base64.stringify(CryptoJS.enc.Utf8.parse(encryptedData));
console.log("base64CipherText ->",base64CipherText)
     

const decryptedBytes = CryptoJS.enc.Base64.parse(base64CipherText);
console.log("decryptedBytes ->",decryptedBytes)
const decryptedText = decrypt(decryptedBytes, secret).toString(crypto.enc.Utf8);
console.log("decryptedText ->",decryptedText)

I am able to do encryption , but when try to do decryption I am getting this error

Decryption failed. Malformed UTF-8 data.

I am just doing decryption to check what data will I receive at backend after decryption.