What can i do if the bank acted unprofessionally and fooled me

Hi, I live in Australia and Recently Visited India for short stay. I wanted to open an Nri account in HDFC Bank. I visited the branch last month on 12th and told them I have a return flight on 7th May and I need an account on urgent basis. They told me it will take only 7days of time, I also told them of it they can open the account by that time only then process my application. They assured me and from then they processed. After three weeks I visited the bank twice and they told me to relax and wait for the account details. After which I tweeted about the same and got the response that I should get the details in 5 working days. I havnt got my account open and they wasted my precious time now I am getting measage to come to bank to collect my atm pin. I want to file a case for the bank as they wasted my precious time and are unapologetic. We do have laws in australia but not sure if there is any law to sue companies like hdfc for such neglegence