You are only allowed to apply for visas via the e-visa website while you are outside of Thailand. You lied on your application, stating that you were in Australia, when you were in fact already in Thailand. While you now have been approved for a retirement visa, it is still not activated. You are still on Visa exemption. The only way to activate this visa now, Ia to exit the country and than renter, showing the immigration officer at the airport tour digital visa. He/She will then stamp you in on it. Then you can apply for a bank account.