Error when decrypting binary data with keys openpgp js?

I use openpgpjs library for node js. I have the following code:

//encryption function 
const options = {
        publicKeys: openpgp.key.readArmored(this.user.publicKey).keys,
        data: data //uint8array data
    };
    return openpgp.encrypt(options);

And decryption function below:

const privKeyObj = openpgp.key.readArmored(this.user.secretKey).keys[0];
    privKeyObj.decrypt(this.user.passphrase);
    const options = {
        message: openpgp.message.read(data), //data is uint8array 
        privateKey: privKeyObj,
        format: 'binary'
    };
    return openpgp.decrypt(options);

but I got an error when trying to decrypt: Invalid session key for decryption

In function Message.prototype.decrypt We have a code:

const keyObj = sessionKey || this.decryptSessionKey(privateKey, password);

But when I encrypted file I used only public key where I can find a session key to decrypt?

via Haygo