Charging Lipo batterys

[Cahill+Son]

I have just bought a LRP pulse R3 charger and a Orion Lipo battery.

I am having problems getting it charged.
The shop i got it from said it comes fully charged so i ran it for a while to partly discharge it.

But now when i try and charge it on the settings the instructions of the charger say it just says it is fully charged and wont charge.
It is obviously not fully charged as the car is not running as fast as it was when i first put the Lipo in.

I just wondering if any one had the same charger who knows what there doing or if anyone can help me at all as i am new lipos.

Any help will be brilliant

Thanks
Nick Cahill