"Please provide a valid zip code or postal code" on Self Solve!! HELP!!?

I keep trying to use Self solve so i can send in an iPhone for repair, but everytime it gets to the shipping, i enter my shipping code, "2170" for my suburb in Sydney, and it keeps saying "Please provide a valid zip code or postal code" it's very frustrating because I've tried a number of things. Yes it's on the Australian store, yes i've tried removing the code from my Apple ID. Yes i've tried puting a different post code, Yes I've tried putting a different name etc. It's not on my side. I've even tried using a different browser, same crap happens.

Can somebody please help me?