1, you need to determine the actual size of the self-adhesive label paper, such as paper labeled 80 mm 48 mm, plus margins may be the actual size of 84 mm 48 mm, in this case in the bar code software settings of the label size should be changed to 84 mm 48 mm.
2, if the paper size is normal, then in the barcode software print settings on the top edge of the space and the left side of the space to fine-tune.