If you have a smart meter or interval meter, you can view your detailed historical data by heading to this page here: https://app.amber.com.au/usage/.
You can customise the date range of the data and export it as well. Once you export your usage data, you'll be sent an email with a CSV. file with some tips on how to interpret the data we've shared with you.
If you have a basic meter, your meter does not read data on 30min increments, so accurate historical data may not be available. Similarly, interval meters are read every 3 months by a technician from your network, so the availability of the data will depend on when your meter was last read.