Sometimes when printing labels, you may have some label be blank instead of printing the address as normal. This is normally caused by there being a space at the end of their address entry.
Go to the Client/Contact information screen for the client, click in their address box, and be sure there is not a space at the end of their address. Also, be sure there is not a blank line after the address entry (hit the down arrow on your keyboard, and if it goes to a new line, then hit Backspace, and keep doing that until it does not go to a new line when you hit the down arrow).
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