Before you can start taking orders, the cash drawer needs to be assigned to a cashier or manager.
To do this, tap on the Manager button in the lower right and enter your pin or swipe your card when prompted. Once you arrive on the Manager page, tap on the "Cash" tab on the left, which looks like this:
Tap on the "Assign Cashier" button, and you'll be prompted to enter the starting cash amount like so:
The cashier will then be prompted to enter their pin or swipe their employee card to assign the drawer to them. Once you've done that, you'll see a "Starting" cash event added in the cash events section like so:
You can then tap on the "Order" button to start an order.