Make sure that the battery charging is really not possible. For example, there are cases when the charging indicator on the screen of the phone remained unchanged, although the charging process in this case took place in normal mode. This may be a result of a failure of the display or software of a mobile phone.
Pick up a PSU and test it. If it's warm or hot, the charging indicator it lights up the problem in this case is really hardware. Also upon successful completion of the charging can be warm and the housing of the mobile phone.
If the charging indicator remains unchanged, and the charger itself also had no signs of life, test the contacts of the cellular phone. They can become clogged with dust and dirt. Soak in pure alcohol a piece of gauze and gently wipe the connectors. First you should power off the device and remove the battery. Also wipe and the charger itself. In any case don't wash contacts with water, otherwise the phone may completely fail.
Inspect the charger cable. Over time, due to jerks and being in a twisted state, it may appear cracks and breaks, it frays and eventually the charger fails. Also a high probability that its use life just came to an end. To waste all their resources could the battery itself, in this case need to be replaced.
Please contact the store where you bought the phone and charger, report available issue. If the warranty is not out, after inspection of the failed components replaced. Otherwise you can buy a new charger, or give the phone to the repair service center yourself.