u/m4xM2023

I need help fast please
Ive just recieved my mtw forged hpa gun and the battery that came with

I tried to charge out but got a CONNECTION BREAK message with an alert and ive got a game soon and really want to try it out before my refund period expires

it was the rebel. 7.4v 300mAh 35c lipo battery

i used the nuprol power np60w smart charger:
It has 3 charging holes with a hole like a castle? with 5 thin pins which is called 4s-1
a yellow hole with 2 large pins in a rectangular/trapizim shape.
and a hole to the right with TEMP labeld with 3 pins

with the settings of Lipo{1} Charge 0.3A 7.4v 2(s)

the charger i used isnt new and ive used NIMH and LIPO batteries on it before.

Help