The connector was not functioning correctly anymore. You needed to flex the connected cable to keep the phone charging. Probably the 5 Volt connection was broken or misaligned. I watched toe following movie on Utube which clearly describes what to do to fix the device.
Double sided mobile phone tape
Plastic opening tool/plectrum/
Samsung Galaxy S Advance I9070 Charging Port Flex Cable Ribbon – ETrade Supply
The steps taken were:Shutdown the deviceRemoved the battery (of course after removing the battery cover)Remove SIM and uSD cardRemove the 6 screws on the back with a small Philips screwdriver (are the same size)Remove outside/rear housing, unlock the clips with your fingernail or plastic opening tool. Start at the bottom.When replacing the back cover make sure to exchange the antenna which is clicked in there.Disconnect and remove the loudspeakerDisconnect the 3G GSM antenna cableLift the volume switch (use the hair dryer to soften the adhesive)Lift the power switchDisconnect the LCD flex cableDisconnect the front cameraRemove the 7th screw on the top sideDisconnect the USB cableThe main board can be removed nowThe SIM and uSD board can be removed from the main board now (only if needed, make sure the clip and pins are aligned when replacing it with a new one)Also the camera can be replaced from the main board now (only if needed)Now for the removal of the USB flex assemblyLift the vinyl tape (carefully)Lift the flex cable (slowly)When removing the bottom part of the USB flex assembly, watch out bcos it is connected to the capacitive sensors of the menu and back buttonsRemove the silicone gasket from the microphone