If you forget your bike key, you can use the Transit app to request ride codes. To link your account, tap on a station marker, then tap the station name an log in with your Divvy user name and password. To ride, find the Divvy card or tap the closest pin on the map, select "Get a Bike" and enter your 5-digit ride code into the keypad of any dock with an available bike to unlock it.
For more information, please see the App page. Once you've successfully entered a ride code, the light on the dock will turn green. This means the bike is unlocked. To remove it from the dock, pull the bike out by the handlebars or lift the bike by the seat to release it.