There may be several reasons for printing blank pages.
1. (most common)The peel-off side should be facing up when feeding the labels, please follow the below picture and don't put it upside down, or the printed page would be blank. 
2. (most common) It's possible that the printer didn't recognize the label size correctly yet. Please press and hold the feeder button on the top until you hear one beep then release, the label will automatically move back and forth to load two labels. Then you can start printing. You may print a print this Sample Label to check. Please click the link for more details
3. Please press and hold the feeder button on the top until you hear two beeps then release, your printer will load one test label. Please check if the test label is normal, if it is, your printer is working well and the problem is with the label or the settings.
4. (For Mac) Please sure the paper size under Print Preferences for label printer is 4*6, not full size (8.5*11 or US letter).
5. Please make sure that you are using the shipping label from Jadens, sometimes the label from other brands does not work,