How to configure ExcelReaderFactory to solve problem of Encoding in c#?

Question

I use ExcelDataReader.DataSet nuggetPackage

var reader = ExcelReaderFactory.CreateReader(stream);
 var conf = new ExcelDataSetConfiguration
                {
                    
                    UseColumnDataType = true,

                    FilterSheet = (tableReader, sheetIndex) => true,

                    ConfigureDataTable = (tableReader) => new ExcelDataTableConfiguration()
                    {
                        EmptyColumnNamePrefix = "Column",
                        UseHeaderRow = false,
                        }
                    }              
                };
                var dataSet = reader.AsDataSet(conf);

I have the data in the dataset but some characters became ? (é => ?, ç => ?)

i try to use ExcelReaderConfiguration but i didn't find how to use dataset with this.

var readerConf = ExcelReaderFactory.CreateReader(stream, new ExcelReaderConfiguration()
                {
                    FallbackEncoding = Encoding.GetEncoding(1252),
                    AutodetectSeparators = new char[] { ',', ';', '\t', '|', '#' },
                    LeaveOpen = false,
                    AnalyzeInitialCsvRows = 0,
                });