When you load in a new direct thermal label, there are two actions that need to take place:
1) Run the automatic label identification on the printer.
2) Set proper label settings on your computer.
3)Run the automatic label identification.
①Disconnect the USB cable from your printer, then turn the printer off.
Press and hold the Feed Button until you hear one beep, then release.
②Printer will determine the gap size and other properties of your label.
③After the determine, re-connect the USB cable to the printer and resume printing.
Check the segment of the video " MUNBYN Introduction Of Feed Button Mode".
2) Set your custom label size
Select or input label width and height that matches label size installed in printer in prompt window.
Go to "Control panel" -> "Devices and Printers"
(Right click on "This PC", choose "Properties", then click on "Control panel"-> "Devices and Printers")
->Right click on "Label Printer" -> choose "Printer Preferences"
-> Go to "Page Setup" -> Select the paper type in "Name"
If there is no label size you need, you can click "New" to create a label size.
Change Paper name and input width and height, click "OK"
The application you are using (e.g. Adobe Reader) could be over-riding your driver label setting and sending the print in a larger / smaller size to the printer. Look for "Page Setup" or "Paper Size" in the print prompt and ensure it is set to the size you want.