You can cancel an order you placed directly with Pollen Mobile at shop.pollenmobile.io if your order has not yet shipped by submitting the Order and Shipping Questions form.
Typically, orders for hardware ship within 1-2 weeks from purchase, so you can cancel your order anytime within that window.
Once your order has shipped, you will need to request a return. Please check out How can I return my order? for more information on that process.