CryptoKit.CryptoKitError.authenticationFailure error when trying decrypt message from 2-d user

Question

I have an error CryptoKit.CryptoKitError.authenticationFailure when the second user trying decrypt message. For the 1-st - works perfect! Cloud you check, what I missed?

Here the code:

func encryptMessage(chatId: String, text: String, completion: @escaping (String?, Error?)->()) {
    do {
        guard let keysModel = DatabaseManager.instance.getKeys(uuid: chatId) else { return }
        let privateKey = try DatabaseManager.instance.importPrivateKey(keysModel.myPrivateKey)
        let publickKey = try DatabaseManager.instance.importPublicKey(keysModel.publicUserKey ?? "")
        let symmetricKey = try prepareKeysPair(privateKey: privateKey, publicKey: publickKey)
        guard let textData = text.data(using: .utf8) else {
            completion(nil, nil)
            return }

        let encrypted = try ChaChaPoly.seal(textData, using: symmetricKey)
        let message = encrypted.combined.base64EncodedString()
        completion(message, nil)
    } catch {
        completion(nil, error)
    }
}

func decryptMessage(chatId: String, text: String, completion: @escaping (String?, Error?)->()) {
    do {
        guard let keysModel = DatabaseManager.instance.getKeys(uuid: chatId) else { return }
        let privateKey = try DatabaseManager.instance.importPrivateKey(keysModel.myPrivateKey)
        let publickKey = try DatabaseManager.instance.importPublicKey(keysModel.publicUserKey ?? "")
        let symmetricKey = try prepareKeysPair(privateKey: privateKey, publicKey: publickKey)
        
        guard let data = Data(base64Encoded: text) else {
            completion(nil, nil)
            return
        }
        
        let sealedBox = try ChaChaPoly.SealedBox(combined: data)
        let decryptedData = try ChaChaPoly.open(sealedBox, using: symmetricKey)
        let rSensitiveMessage = String(data: decryptedData, encoding: .utf8)!
        
        completion(rSensitiveMessage, nil)
    } catch {
        completion(nil, error)
    }
}

func prepareKeysPair(privateKey: P256.KeyAgreement.PrivateKey, publicKey: P256.KeyAgreement.PublicKey) throws -> SymmetricKey {
    let iv = "31348c0987c7".data(using: .utf8)
    let sharedSecret = try privateKey.sharedSecretFromKeyAgreement(with: publicKey)
    let symmetricKey = sharedSecret.hkdfDerivedSymmetricKey(
        using: SHA256.self,
        salt: iv ?? Data(),
        sharedInfo: Data(),
        outputByteCount: 32
    )
    
    return symmetricKey
}

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