The printer app cuts a wide label into equal parts. See where the cuts will land, and move them so they don't go through barcodes or text.
Drop a label image here, paste it, or
No label handy?
Make the label longer or shorter at either end. Slide outwards to add blank space, inwards to cut some off.
The red lines are where the paper gets cut. If one goes through a barcode, drag that part left or right until it is clear.