Parsing XML file in .NET

Question

I want to get from XML file one or list of records from https://dchrs.com.pl/wp-content/themes/Lucid/doc/notowania.xml

Shortly XSD schema looks like:

<?xml version="1.0" encoding="utf-8"?>
<!-- Created with Liquid Technologies Online Tools 1.0 (https://www.liquid-technologies.com) -->
<xs:schema attributeFormDefault="unqualified" elementFormDefault="qualified" xmlns:xs="http://www.w3.org/2001/XMLSchema">
  <xs:element name="notowania">
    <xs:complexType>
      <xs:sequence>
        <xs:element name="data_wygenerowania" type="xs:string" />
        <xs:element name="kurs_euro" type="xs:decimal" />
        <xs:element name="kategorie">
          <xs:complexType>
            <xs:sequence>
              <xs:element maxOccurs="unbounded" name="kategoria">
                <xs:complexType>
                  <xs:sequence>
                    <xs:element name="nazwa" type="xs:string" />
                    <xs:element name="pozycje">
                      <xs:complexType>
                        <xs:sequence minOccurs="0">
                          <xs:element maxOccurs="unbounded" name="pozycja">
                            <xs:complexType>
                              <xs:sequence>
                                <xs:element name="nazwa" type="xs:string" />
                                <xs:element name="jednostka" type="xs:string" />
                                <xs:element name="cena_pln" type="xs:string" />
                                <xs:element name="cena_euro" type="xs:string" />
                              </xs:sequence>
                            </xs:complexType>
                          </xs:element>
                        </xs:sequence>
                      </xs:complexType>
                    </xs:element>
                  </xs:sequence>
                </xs:complexType>
              </xs:element>
            </xs:sequence>
          </xs:complexType>
        </xs:element>
      </xs:sequence>
    </xs:complexType>
  </xs:element>
</xs:schema>

I have created a few classes like:

• Flower:

using System.Xml.Serialization;
    
[XmlRoot(ElementName = "pozycja")]
public class Flower
{
    [XmlElement(ElementName = "nazwa")]
    public string Name { get; set; }

    [XmlElement(ElementName = "jednostka")]
    public string Unit { get; set; }

    [XmlElement(ElementName = "cena_pln")]
    public string PricePln { get; set; }

    [XmlElement(ElementName = "cena_euro")]
    public string PriceEuro { get; set; }
}

• Flowers:

using System.Collections.Generic;
using System.Xml.Serialization;

[XmlRoot(ElementName = "pozycje")]
public class Flowers
{
    [XmlElement(ElementName = "nazwa")]
    public List<string> Flower { get; set; }
}

• TypeOfFlower:

using System.Xml.Serialization;
    
[XmlRoot(ElementName = "kategoria")]
public class TypeOfFlower
{
    [XmlElement(ElementName = "nazwa")]
    public string Category { get; set; }

    [XmlElement(ElementName = "pozycje")]
    public Flowers Flowers { get; set; }
}

• and FlowerConnector to fetch them from Url:

using RestSharp;    
using System.IO;    
using System.Threading.Tasks;   
using System.Xml;    
using XmlSerializer = RestSharp.Serializers.XmlSerializer;

namespace FlowerShop.ApplicationServices.Components.Flowers
{
    public class FlowersConnector : IFlowersConnector
    {
        private readonly RestClient restClient;
        private readonly string baseUrl = "https://dchrs.com.pl/";
        string getUrl = "https://dchrs.com.pl/wp-content/themes/Lucid/doc/notowania.xml";
 
        public FlowersConnector()
        {
           this.restClient = new RestClient(baseUrl);
        }
    
        public Task<Flowers> Fetch(string name)
        {
            var request = new RestRequest("wp-content/themes/Lucid/doc/notowania.xml", Method.GET);
            var queryResult = restClient.ExecuteAsync(request);
            var flowersXml = ;  // ???        
        }
    }
}

After a few trials I got to give up.

Can somebody help me out with solving this problem?

[Edit] Here's what I've tried:

using RestSharp.Serialization;
using RestSharp.Serializers;
using System.Xml;
using System.IO;
using System.Xml.Serialization;
using XmlSerializer = RestSharp.Serializers.XmlSerializer;

namespace FlowerShop.ApplicationServices.Components.Flowers
{
    public class FlowersConnector : IFlowersConnector
    {
        private readonly RestClient restClient;
        private readonly string baseUrl = "https://dchrs.com.pl/";
        string getUrl = "https://dchrs.com.pl/wp-content/themes/Lucid/doc/notowania.xml";

        public FlowersConnector()
        {
            this.restClient = new RestClient(baseUrl);
        }

        //public async Task<Flowers> Fetch(string name)
        //{
        //    var request = new RestRequest("wp-content/themes/Lucid/doc/notowania.xml", Method.GET);
        //    var queryResult = await restClient.ExecuteAsync(request);


        //}

        public Task<Flowers> Fetch(string name)
        {
            var request = new RestRequest("wp-content/themes/Lucid/doc/notowania.xml", Method.GET);
            var queryResult = restClient.ExecuteAsync(request);
            var flowersXml = XmlConvert<Flowers>.ListDeserializeObject(queryResult);

            return new Flowers();
        }
    }
}

//////private readonly string apiUrl = "https://dchrs.com.pl/wp-content/themes/Lucid/doc/notowania.xml";

public class XmlConvert<T> where T : new()
{
    //Serialized objects become XML strings
    public static string SerializeObject(T myObj)
    {
        var xmlStr = string.Empty;
        if (myObj != null)
        {
            XmlSerializer xs = new XmlSerializer(typeof(T));
            using (var stringWriter = new StringWriter())
            {
                xs.Serialize(stringWriter, myObj);
                xmlStr = stringWriter + "";
            }
        }
        return xmlStr;
    }

    //Serialized objects become XML strings
    public static string SerializeObject1(T Object)
    {
        var xmlStr = string.Empty;
        if (Object != null)
        {
            XmlSerializer xs = new XmlSerializer(typeof(T));//Initializing XMLSerializer object
            MemoryStream stream = new MemoryStream();
            XmlTextWriter writer = new XmlTextWriter(stream, System.Text.Encoding.UTF8);
            //writer.Formatting = Formatting.None;//  Do not apply special format settings. This is the default value.
            writer.Formatting = Formatting.Indented;  //Set indent.
            xs.Serialize(writer, Object);
            stream.Position = 0; //  Get or set the current location in the stream. Must be set, otherwise the default last position, the data in the stream is not received
            using (StreamReader reader = new StreamReader(stream, System.Text.Encoding.UTF8))
            {
                string line;
                while ((line = reader.ReadLine()) != null)
                {
                    xmlStr += line;
                }
            }
            writer.Close();
        }
        return xmlStr;
    }

    internal static object ListDeserializeObject(RestSharp.IRestResponse queryResult)
    {
        throw new System.NotImplementedException();
    }
}

error