If you are using Epson Receipt Printer (TM U220) you need to setup your printer to avoid getting wasted paper caused by Header and Footer printing.
Please follow below instruction depending on the browser you use
I. Chrome Print Setup
Type Ctrl + P (Print), Make sure Headers and Footers is not clicked
II. Firefox Print Setup
Goto Print - Page Setup
Specify Zero Margin and Blank Header & Footer
Please visit DealPOS Article about this : Setting Up Margin Printer on Browser