How to encode QR with TLV values in C#

Question

I have this code in C# which use it to generate a QR code base64 and want to decode the output into original TLV values as strings, for example in my code I am generating the QR code encode base64 and want to get back with original TLVs tags and store it in separate string per each value

using System;

namespace tlvgenerator
{
    class Program
    {
        static void Main(string[] args)
        {
             
            string Name = GetHexString(1, Encoding.UTF8.GetBytes("Name"));              //Tag1
            string Serial = GetHexString(2, Encoding.UTF8.GetBytes("123456789123456789"));             //Tag2
            string dateTimeStr = GetHexString(3, Encoding.UTF8.GetBytes("2022-07-17T11:20:51Z"));  //Tag3
            string ModelNum = GetHexString(4, Encoding.UTF8.GetBytes("12356.123"));                  //Tag4
            string PartNo = GetHexString(5, Encoding.UTF8.GetBytes("9782.45"));                    //Tag5
            string SN = GetHexString(6, Encoding.UTF8.GetBytes("abcdef12345"));//Tag6
            string Shelf = GetHexString(7, Encoding.UTF8.GetBytes("A2F345"));//Tag6
            string Area = GetHexString(8, Convert.FromBase64String(Area));                      //Tag7
            string Building = GetHexString(9, Convert.FromBase64String(Building));                       //Tag8

            string decString = Name + Serial + dateTimeStr + ModelNum + PartNo + SN + Shelf + Area + Building;

            string finalQR = HexToBase64(decString);
            Console.WriteLine(finalQR);

        }

        static string GetHexString(int tagNo, byte[] tagValue)
        {
            string strTagNo = string.Format("0{0:X}", tagNo);
            string tagNoVal = strTagNo.Substring(strTagNo.Length - 2, 2);

            string strTagValueLength = string.Format("0{0:X}", tagValue.Length);
            string tagValueLengthVal = strTagValueLength.Substring(strTagValueLength.Length - 2, 2);

            return tagNoVal + tagValueLengthVal + BitConverter.ToString(tagValue).Replace("-", "");
        }
        static string gethexDec(Int32 TagValue)
        {
            string hxint = String.Format("0{0:X}", TagValue);
            return hxint.Substring(hxint.Length - 2, 2);

        }
        public static string HexToBase64(string strInput)
        {
            try
            {
                var bytes = new byte[strInput.Length / 2];
                for (var i = 0; i < bytes.Length; i++)
                {
                    bytes[i] = Convert.ToByte(strInput.Substring(i * 2, 2), 16);
                }
                return Convert.ToBase64String(bytes);
            }
            catch (Exception)
            {
                return "-1";
            }
        }
    }
}