1. Ensure you are using LabelRange's original power cable/adapter to connect.
2. Open the printer cover to check if anything is stuck. Remove any obstructions and clean.
Try to always wipe down the print head when you switch labels so the stickers don't get stuck when printing.
3. If you are using BT620 Printer and using UPS labels, please set your print speed to "2" and density to "2" then try your print again.