Method 1 - Check Layout
Open your printer cover, press the cover-open buttons located on both sides of the printer to lift and open the cover.
Carbon paper: Make sure the carbon paper is flat and smooth when touching the print head and align to the centre.
Label paper: Make sure the paper guide to be the same width of label roll and pull out the label roll till it passes the gap sensor and cutter.
Method 2 - Bad Hardware
Last, if you still can't solve your problem by using the above-mentioned methods. It's possible that the label printer could be at fault. Please contact the relevant technical staff.