Did you use OTG connection? Did you get a warning message in the app when you tried to switch in sport mode?Can you help me please ?
My spark it not working to sport mode, when I turn on sport mode switching not worked.
Thank
If the answer is yes for both questions then try to connect with wifi and in the settings menu you will see an option for advanced flight modes. Turn that on and sport mode will be available again.
If you have advanced flight modes the problem will be something else.