Good afternoon.  The spark control has an error.  When you press the power button once (normal procedure to control the charge level), it turns on and flashes only the first LED, as if it had a minimum charge.  When connected to charge, the same thing happens, the controller turns on automatically and only the first LED flashes, without charging.  I commented that I did not perform any update, and also does not respond to the reset of the controller.

Did you leave it on charge long enough? Is your USB cable ok, or charger?

Hi, thank you for reaching out and we do apologize for the inconvenience. Can you please try to leave the RC on the charger for about 1-2 hours and check if the problem persists? Also, please make sure that the charger that you are the original charger that comes with the package. Please keep us posted. Thank you!

How long havent you used it?
Or is it a new controller?
Try it with a 2A charger from a phone for a little time, perhaps he battery needs a bit power  to get activated!

As an addition to S-e-ven’s post above invest in a USB monitor/meter. These devices are cheap and show the Voltage, current draw, and millAmps drawn. This way you will be able to determine if the controller is actually charging, you’ll see an increase in the milliamperes drawn, and provide more info if there is a problem.

Regards

Nidge.