"Waiting too long for Accounts Department to answer the phone."

I am writing on behalf of an overseas student who was sick and had to spend a night at Box Hill Hospital. I have tried twice today to call the Accounts Department to so that his visiting Aunt can claim the account from Medicare before she returns home (overseas). I have had to wait 10 minutes on each occasion, but haven't had anyone answer - not even a message to say when someone will answer. It shouldn't take that long for someone to answer the phone in the Accounts Department. His Aunt just wants to get the bill and Medicare refund before she leaves the country.