Segway-Ninebot F-Series Electric Scooter Faulty / Error 21

Selling a Segway-Ninebot F-Series electric scooter as-is for repair or spare parts.
​The scooter powers on, the display screen lights up, and electronics function, but it develops a fault/slowdown during use and displays Error 21 (BMS / Battery communication error).

​Key Details & History:
​Status: Powers on normally, but shuts down / trips Error 21 after riding / under load.

​Modification: The bottom deck area was previously silicone-sealed by a repair shop for waterproofing.

​Body & Frame: In good physical condition with normal cosmetic wear. Folding mechanism and deck are solid.

​Original Segway Charger included

​Terms:
Sold as-is (faulty) for someone who wants to repair it or use it for spare parts.

​Collection:
Collection only from home address in Naas, Co. Kildare.
Cash or Revolut on collection.