iPhone not charging? iPhone dust in charging port failed? It's probably dust.

iPhone lightning ports are pone to getting clogged with dust that compacts and eventually stops it from charging.

You really have to dig into the bottom and sides of the port to get it all out. Keep clearing especially at the sides around the little clips until you can put your cable in and you hear the click. 

Props to:

http://mendmyiphone.co.uk/

I contacted them about a repair and was given this tip over the phone for free.