Recently, the throttle stopped working while others look normal, so I contacted customer service and replaced the controller myself.
Immediately after the replacement, the throttle seemed to work for a few seconds, but soon the battery level dropped back to one bar and stopped functioning.
The power turned off, and when I tried to turn it back on, I heard a small spark-like sound coming from the battery about once or twice per second while the battery level on the left controller dropped to 1 and blinking. So for now, I've disconnected and removed the battery. Anyone experienced similar issues?