Iphone 4 charger won't go all the way?

My iphone don't charge and i found that my charger plug won't go all the way and i can see a little gap when plugged to my iphone 4.

How can make it to charge again?

If you didn't get the charger with the iPhone or from the apple store it might be a fake. There are a lot of fake apple things going around lately, especially chargers. They are dangerous so I would throw it away and buy a new one. If it is a legit charger though you should take it to the apple store for them to have a look at it.

Go to a nearest apple store and get the charger checked or else for the time being use your USB CABLE / DATA TRANSFER CABLE to charge your iphone from computer.