If the SSID for your camera does not appear in the Wi-Fi settings menu on your phone then here are two ways to make it appear:
After 3 minutes of the camera being powered on, the WiFi feature will automatically be disabled. Restart the camera to re-enable the WiFi feature for it appear in the Wi-Fi settings menu on your phone.
The Sena Camera App requires your phone to support 5 GHz WiFi to connect to the camera. If your phone does not support 5 GHz WiFi then you can use this FAQ to switch to 2.4 GHz WiFi.