I know this is a bit late to be replying. but we recently purchased a lot of 211 mobile phones that were faulty. most were Huawei we fixed all without replacing chargers or batteries except 6. first put the phones on charge for 1 hour. if the phone starts loosing power or wont charge or even charges then shuts down as soon as you take the charger from the socket. or maybe just charges when it wants. I think I can solve this problem with some easy steps.
take the charger of, turn of phone, remove the battery,
put charger back in without the battery turn it on. if you don't get a screen try searching the cord for damaged spots as this is your problem. if you get a screen its not the charger. and you will need to test battery. best way we found to do this is to unclip one single Christmas light fold the small gold wires out and touch them on the battery prongs one wire at each end weather its 3,4 or 5 squares. if there is no light at all try jump starting it with a usb cable plugged in folding all wires over and using just red and black red to + and black to - for 20 seconds. we had 48 phones going by this stage the other 157 we put cardboard behind the bottom of the battery this forced it against the prongs. once we found they worked we cut small plastic and glued it. I guess this happens with phones that get kept in pockets. or the sun heats them up and the frames or batterys buckle just enough so you cant see it. sort of like a car if the battery terminals are not tight it sometimes plays up well I hope this helps anyone in future