Ninebot ES1 autonomy
 

Hi everyone! I've bought the Ninebot ES1 a month ago and I'm very satisfied by this product. However, I'm a bit confused about the autonomy of the battery. All the reviews say that a charge lasts for 25 km, but I barely succeed to reach 15 km, even though I am using exclusively the Eco mode and there are no slopes on the road I use.
What do you this about this issue? Thanks for your help!