Mi Air 13.3" 2016 - Non charging battery FIX - Bad battery connector

I get that same problem, but in my case it happened from the first day I bought it (2018). If the charge is 95% it doesn't want any more charge to reach 100%.
I've noticed that the battery charges again when it's capacity drops under 94% or so. Then it starts to charge again to 100%.

Example: It has 100% battery. Y play for a while and the battery drops to 97%. I plug the power, but it rejects to be charged. I can use it and the charge won't go down or up. Then I unplug it, use it, and the charge drops to 92%. I then I plug the power and the the laptop will charge to 100%.