If you are using your mobile phone for a long time than one thing will surely happen that is the problem in charging port. You plugged in your phone for charging but it is not charging. Before changing your charger or cable you should check the port. After long use, your phone’s ports will begin to get clogged with lint and dirt and god knows what. Most of the time this will go unnoticed until it begins to cause significant problems.
Charging port cleaning
You can clean this port on your own. Most people suggest using a toothpick to clean micro USB port. But that is not right thing as toothpick can break inside port if you use it aggressively causing a serious damage to the port. Instead, try using some eject tool. That is long enough and made of metal which is impossible to bend or break so there is no possibility that it can break inside the port. Work the SIM eject tool into the port at an angle and gently scrape the lint out. You’ll see it fall out in clumps–and be aware that there will probably be more packed inside that you expect.
After you are done, plug in your cable. You’ll immediately notice that there is now a much firmer connection between cable and port then there’s been in a long time. So next time if your mobile is not charging clean it's port first before going for a new charger.