Adding a payment card in the app is by default mandatory to start a trip and enter a promo code in the app as well. This is to ensure more security for your service and a way to charge the client at the end of a trip and also after his promo bonus amount is used up.
In case you do not want to force your customers to save a card in the app before they can use a promo code and add a bonus in their wallet, please submit a request to help@atommobility.com to disable this setting in the system backend for your service.
NB! ATOM is not liable for any losses your service might sustain in case you choose to disable mandatory card adding functionality.