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.
1)Run the automatic label identification.
①Disconnect the USB cable from your printer, then simply press and hold the Feed Button for 3 sec.
②Printer will move the label back and forth to determine the gap size and other properties of your label.
③When the label is at the tear off point; re-connect the USB cable to the printer and resume printing.
Check the video "Automatic label identification"
2) Set your custom label size
Select or input label width and height that matches label size installed in printer in prompt window.
Open "Devices and Printers" -> right click on "Label Printer"-> choose "Printer Preferences"
You can choose the size you need in "Paper Name". If the size you need is not listed, then click "Manage" to create needed size. (Input the size of "Paper Width", "Paper Length" and "Paper Name", then click "Save" to archive.)
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.