How do I handle complex JSON information inside a CSV file?

Question

I´m trying to create an import of CSV data into my Blazor project in .NET7 but I´m facing issues with how to handle the data on one specific field in the CSV and can´t seem to get around the issue.

The CSV data I´m trying to import typically looks like this: First there are columnHeaders for "Name", "Address", "City" etc. and finally "Notes". Then comes the data values using ; as the delimiter. I´m able to read in all fields except "Notes" because it has a different format

NameValue;AddressValue;CityValue;"{
  "Information": "",
  "InformationHistoryFixed": "",
  "customerNotes": [],
  "bookingNotes": []
}"

The only thing in the "Notes" header I manage to use from this is the very first "{ then comes a row break that cuts me off from the rest of the data.

Right now I´m using an InputFile through a file uploader/picker I then run a method to process the data which is where the headers are assigned and the rest of the data is sent to a DataTable to read values in each cell.

private async Task ProcessImportData()
{
    if (uploadedFileStream != null)
    {
        using (MemoryStream memoryStream = new MemoryStream())
        {
            await uploadedFileStream.CopyToAsync(memoryStream);
            memoryStream.Position = 0;

            using (ExcelEngine excelEngine = new ExcelEngine())
            {
                IApplication application = excelEngine.Excel;
                application.DefaultVersion = ExcelVersion.Xlsx;

                using (Stream inputStream = memoryStream)
                {
                    IWorkbook workbook = application.Workbooks.Open(inputStream);
                    IWorksheet worksheet = workbook.Worksheets[0];
                    
                    columnHeaders = new List<string>();
                    for (int i = 1; i <= worksheet.UsedRange.LastColumn; i++)
                    {
                        if (!string.IsNullOrEmpty(worksheet[1, i]?.Text))
                        {                                
                            string[] headers = worksheet[1, i].Text.Split(';');                                
                            foreach (string header in headers)
                            {
                                columnHeaders.Add(header.Trim());
                            }
                        }
                    }
                 
                    DataTable dataTable = new DataTable();
                    foreach (var columnHeader in columnHeaders)
                    {
                        dataTable.Columns.Add(columnHeader);
                    }

                    for (int i = 2; i <= worksheet.UsedRange.LastRow; i++)
                    {
                        DataRow dataRow = dataTable.NewRow();
                        for (int j = 1; j <= worksheet.UsedRange.LastColumn; j++)
                        {
                            dataRow[j - 1] = worksheet[i, j].Text;
                        }
                        dataTable.Rows.Add(dataRow);
                    }

                    string jsonString = GetJsonStringFromWorksheet(worksheet);

                    ProcessDataTable(dataTable);

                }
            }
        }
    }
}

It then goes to ProcessDataTable where it should create a model and fill in Name, Address, Notes etc:

private void ProcessDataTable(DataTable dataTable)
{
    processedData = new List<ImportCustomerModel>();

    // Loop through each row in the DataTable, skipping the first row with column headers
    for (int i = 0; i < dataTable.Rows.Count; i++)
    {
        DataRow row = dataTable.Rows[i];
        ImportCustomerModel model = new ImportCustomerModel();

        string line = row[0].ToString();           

        if (columns.Length >= 21)
        {            
            model.Name= columns[0]?.Trim();
            model.Address= columns[1]?.Trim();
            model.City= columns[2]?.Trim();
            ....
            model.Notes= columns[20]?.Trim();
          
            processedData.Add(model);
        }
    }
}