Do you have the version of the battery that holds batteries with tabs or springs? It's been established that the tabs version led to problems, vs i'm unaware of problems with the springs version. I would start there, because if you have the tabs version, contact LTWOO and get a springs version. The battery housing weighs nothing so shipping it to you should be super cheap for them. And in the meantime, you can add shims to increase the pressure / tension on the system.

It is unlikely that any of your group is broken, stuff typically doesnt randomly breaks just like that, especially when it's new and you weren't doing anything weird with it.

Thanks Serge_K. I have the battery with the springs version insert. I hope you are right, and nothing is broken. I am trying to exercise warranty through "LTWOO Official Store" on Aliexpress, but so far no luck.

My eRX Rear Derailleur stops working during ride. Anybody have a fix?

One hour into ride, rear derailleur “crashed” in gear 12. Derailleur would not come out of 12th gear. There was noise coming from the derailleur, but no movement. Front derailleur kept working.
When I plugged the charger onto the derailleur, nothing changed. It will not come out of 12th gear so I can't recalibrate via the App. Front derailleur still working.

Is there something I can do? Do I need a new rear derailleur?

Thank you for your help!