Ninebot F2 Battery Dies Quickly Even When Not in Use

I purchased my Segway Ninebot F2 scooter in May 2025, and I have recently been experiencing a serious battery problem. As of November 10, 2025, I noticed that even after fully charging the scooter, it only lasts one to two hours, whereas before I could easily use it throughout the entire day. In addition, the battery drains very quickly even when the scooter is not in use. I have not seen any error messages or warning indicators on the battery display or screen.

I typically use and store the scooter outdoors. I still have both the warranty certificate and the invoice. Since the issue is new, I have not taken the scooter to a service center yet; however, when I called Segway customer service, they gave me a number to contact, but I was unable to reach anyone and did not receive any response. I have not been charged any service fees so far.

Under the warranty, I am requesting a free repair for this battery issue. I urgently expect support and a clear solution.