PrintLabel does not print correctly in Bartender 2022

Question

Below is part of my code. And garbage characters are printed together. I don't know how to solve this problem.

        lock (engine)
        {
            bool success = true;

            format.PrintSetup.IdenticalCopiesOfLabel = 1;

            if (format.PrintSetup.SupportsSerializedLabels)
                format.PrintSetup.NumberOfSerializedLabels = 1;

             format.SubStrings["Serial"].Value = serial; // serial is string
       
 
            format.PrintSetup.PrinterName = printer;
            format.PrintSetup.UseDatabase = false;
            int waitForCompletionTimeout = 10000; 
            Result result = format.Print(appName, waitForCompletionTimeout);
            if (result != Result.Failure)
            {
                return 1;
            }

        }

THe Output is:

Please advise on how to solve this problem.