AirPods (Second gen - wired charging)

My left AirPod does not work at all. No sound is produced from the AirPod although my right AirPod works just fine. When I put just my left AirPod in, sound plays out loud & the “headphones symbol” at the top of my iPhone does not appear. My left AirPod does still charge though... I’ve tried disconnecting and reconnecting it but it still doesn’t work 🤨🤨

What should I try to fix this problem ?