Im still having this issue. I click print label and it opens a new tab which has my label, but its on an 8.5x11 formatted sheet which doesnt work with a 4x6 thermal label printer. I have tried EVERYTHING you have mentioned and even contacted shopify support to no avail. I am the sole owner and only person on my account as well so permissions shouldnt have anything to do with this. I have tried voiding the label and repurchasing to see if I could switch it in the "order flow" and this option never came up. I tried going into the shipping settings and it didnt let me select the 4x6 label format.
SOMEONE PLEASE HELP!!!!
Why is this such a big issue with shopify's system?!
This was my issue as well. After contacting Shopify for nearly a week of back and forth emails, they still couldn't help or solve the issue.
I did indeed fix it, but I have no clue how it happened. I simply clicked to purchase a label and the next menu all of a sudden gave me the blue button to change the printing format, and from then on it has defaulted to the 4x6 format. Very frustrating they cant fix it or help diagnose this error that a ton of people seem to be having when they're one of the largest small business platforms in the world.