Carbs are reported differently depending on if you are using US or Australian food data.
US food labeling requirements are that the total grams of carbohydrates include grams of dietary fiber (Total Carbs). When the app is set to Australian food data, the database follows Australian food labeling requirements of reporting the total grams of carbohydrates in a portion of food minus its grams of fiber (Net Carbs).
Currently, the total carbs value is reported as 0 grams of carbs when the app is set to display Australian food data. In the future, only the corresponding value for the region will be displayed.