In the old days we used to always use the capital city in our address. For example, if you lived in a suburb of Brisbane you would list your address as 34 Main Road, Clayfield, Brisbane, Queensland, Australia 4011. This is a ficticious address, just to give an example. Now the Post Office (and others) do not want the Capital City, just the suburb and postcode. So If the buyer has "Brisbane" as in this example. It comes up as an "invalid address" if you try to print a postage label.
I'm not sure what problems you are coming across, but this is the main one I encounter.
In my own life, my landline phone number is "invalid" in many situations, because it is not a mobile, and there seems to be some law I am not aware of that you must own one. Also my address comes up as "invalid sometimes" because I spell it as the street sign says, and others insist that a Street has to be St and that "Street" makes it an invalid address.
I come from an era that insisted on everything being correct, so I find it hard to cope with all the abbreviations. I really wonder if future generations will even know what a fireman is or a service station is, or will it be forever changed to firies and servos.
