Reason①: Your labels are loaded in upside down
Please ensure your labels are properly loaded. The print side is facing up.
Reason②: Ensure your labels are "Direct Thermal" labels.
Reason③: Try to print out test page
-> Press the Feed Button (the top circular button) and hold it until blue light flashes once, then release. Printer will print a test page. If test print looks good, please try to print your label again.