Reason①: Changing your label type and size are the main causes for printer skipping labels or continuously feeding
Disconnect the USB from your printer. Check the segment of the video " MUNBYN Introduction Of Feed Button Mode".
Let the printer re-learn your label. Then change your label type, size on your computer, then re-connect the USB to the printer.
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"
-> You can choose the size you need in "Paper 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"
Notice: The application you are using (i.e. Adobe Reader) could be over-riding your driver label setting and sending the print in a larger/smaller size to printer. Look for "Page Setup" or "Paper Size" in the print prompt and ensure it is set to the size you want.
Reason②: The sensor which detects the paper, is covered by dust and that causes the detection is incorrect
You can check this video to know: How to clear the Printhead
Turn off printer. Open the Cover and use the alcohol pads to clean the sensor. (Any 70% Alcohol pad would work.) Let 2-3minutes for components to dry, then close the Cover and turn Label Printer back on.