There are paper jams or label prints only half and stops

If label is getting stuck (usually during printing something really dark such as a barcode or a thick straight line), this is most likely due to the high print density of your label. This causes the label to get too hot and get stuck to the Printhead. In fact, different labels require different heating temperatures. Set your print speed to 

"4 in/sec" and density to "2" and try print again. If the label is too light, increase the density by 1.

For Mac

①Select "Printer Features" in "Preview" 

②You can change the printing speed and the Darkness of your printing

(Larger number means higher Darkness)

For Win

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 the "Option"

-> You can change the printing speed and the Darkness of your printing

(Larger number means higher Darkness)