I Have A 2013 MacBook Air that refuses to charge. I continue to use it once it says that it has no charge left. What do I do? I received this brand new laptop yesterday and today the charger isn't responding to being plugged in. (The lights aren't flashing as they should be). The battery icon on the upper right corner has a big X inside of it indicating that there is no battery charge left. However, I continue to use my macbook air as if it were charged normally. I don't know what to do. Please help.
It should not be on a "new" MBA but it is possible.

Reset your SMC (System management Controller) that has to to with Battery and charging.

Shut down the computer.
Plug in the MagSafe power adapter to a power source, connecting it to the Mac if its not already connected.
On the built-in keyboard, press the (left side) Shift-Control-Option(alt) keys and the power button at the same time.
Release all the keys and the power button at the same time.
Press the power button to turn on the computer.  


If no sucess bring or send it back for repair.