serilog unique logger asp.net webform 4.8

Question

How can I add q unique serilog logger in my webform app? Because I am doing this in the Load and it is create a new logfile everyTime. I want to log in a same log file. I am using 4.8 .net framework

     public partial class TransferForm : System.Web.UI.Page
    {
 protected void Page_Load(object sender, EventArgs e)
        {
            Log.Logger = new LoggerConfiguration()
            .MinimumLevel.Debug()
            .WriteTo.File(
                  _logFilePath, rollingInterval: RollingInterval.Day, 
                   rollOnFileSizeLimit: true
                         )
            .CreateLogger();
            _logger = Log.Logger;
        }
     }