Thank you for the reply FaeryBee.
Shes getting a seed mix which is the most popular on amazon here and generally the only one you can buy in local stores: ??????????????? / ???????????
I give her a vegetable called komatsuna (translated: Japanese mustard spinach), a few times a week.
She used to have a mineral block in her cage a year or so ago but she wasn't eating it much so we removed it.
I've never given her or my previous budgies egg food before, but I will have a look at some of the threads here and give it a go.
I've asked the vet and several bird shop owners whether just seed is enough whom all seem to say it is, however it obviously isn't.
I've just ordered her a cuttlebone, new mineral block, pellet stick, and a different bird food called Zupreem fruit blend. Hopefully she can get her nutrition, pretty colors and flight feathers back soon!
Re: Justmoira, the vet we go to focus mainly on cats and dogs but say they also do small birds. Unfortunately there isn't an avian vets nearby without having to take the subway for a fair while, which I'm scared is too stressful for Kiwi.
Hopefully these nutrition changes will help her.