Specification of B1 Labels:
Size: 0.55x1.18 inches (14x30mm), 210 labels each roll
Label roll diameter: 1.6 inch
The gap between the label tape: 0.3 inch
Make sure the diameter of the label tape is less than 1.6 inches, or it can't fit inside the B1 label maker.
And check if the gap between the label tape is between 0.24-0.3 inch, or it causes printing issue due to inaccurate paper feeding.