Issue: I have an iPhone 6S and for some reason it is not charging. It was charging just last night. At first, I thought the charger was faulty but so I tried it on a friends iPhone and it was able to charge it and so it is not the charger. Please help!
Cause: The charging port area in the iPhone, or any phone for that matter, can gather a lot of dust; and sometimes pieces of paper or hair can get in there as well. As you continuously push the charger into the phone to charge it, it compresses the dust or pieces of items there until it reaches a point where the charger is not able to get good contact to charge the phone.
Solution 1 : Get a thin pointed object like a sewing needle or thumbtack and use it to clear all the debris that has collected inside the charging port. After everything has been cleared, connect the charger to the phone to see if it is working.
Solution 2: If Solution 1 does not work, then there could be problems with the charging pins inside the charging port. You can use the thumbtack or sewing needle to try to straighten them or send it to a repair shop for further diagnosis and repair.
Solution 3: If your phone is not charging and Solution 1 and Solution 2 are not able to resolve it, then it probably means your phone is dead as a result of moisture damage or other causes and so you will need to get another phone.