Specific settings may need to be adjusted on your transponder to properly trigger, receive, and display traffic information. Contact your certified avionics technician for more information on adjusting these settings. If you have Stratus 1 you will only receive single-band 978 MHz traffic.
Make sure that you are running the latest version of ForeFlight Mobile. Next, connect to your Stratus portable receiver and check on the Stratus Status page in ForeFlight to ensure that the device is running on the latest firmware version. Firmware upgrades are done from the Stratus Status page by tapping on the firmware version. Finally, ensure the Traffic layer is turned on in ForeFlight.