Letters are bleeding or the print quality is not good when printing on narrow labels. (iPrint&Label)
Templates are for commonly used label and tape sizes. Therefore the print result may not be as good when using narrow tape. It may look better if you make letters bold.
How to make letters bold:
Tap the text box and tap font icon on function bar.
Select bold style.
If this doesn't solve the problem, it is recommended that you try and print on wider tape.