iphone 4 repair

[Hpi_guy]

my iphone went for a swim in my swimming pool, luckily water only got in through the charging port, tried to turn it off straight away buy it would keep turning it self on, i then proceeded to do the usual, wrap it in kitchen roll and stuff it into a sock and swing it about for a bit then left it in a tub of rice for a few days, it has cleared all the water out of the phone and screen but the problem now is that the phone wont accept any charge or stay turned on for more than 30 seconds on charge and 3 seconds off charge, when it turns off it acts as if the battery has been disconnected and wont turn on again until it is plugged into the charger