Dear Sir,

You need to make sure the following:

1. Your printers are connected with QZ Tray Sample.
2. Make sure, Correct printer names are added in the following fields in register settings:
   1. QZ Receipt Printer Name
   2. QZ Kitchen Printer Name
   3. QZ Bar Printer Name
3. Make sure if Digital Certificate & Private Key added in the register settings is correct
4. Make sure if “Print Receipt” option is on “Yes” in register settings.