When connected to the Stratus WiFi, open ForeFlight Mobile, tap MORE > DEVICES > STRATUS and confirm that "Use as GPS" is ON.
If the switch is ON but you still see "No Fix" on the Maps page, with the plane positioned on the ramp with a clear view of the sky, this issue is most likely caused by a hardware/installation error and you should troubleshoot it directly with your Avionics shop/installer. The Avionics shop/installer should carefully inspect the cable, plugs, and pins, to ensure they are wired per the Appareo installation instructions. Of note, we have seen this symptom when the cable between the ESG/ESGi and the Stratus 2S/S was incorrectly wired, with pins 6 & 7 reversed.
If needed, your Avionics shop/installer can contact Appareo technical support for assistance with troubleshooting this issue.