My Aunt recently gave me her Tocco F480, and it was working fine. One day, its battery finished and i had the usb for it so i connected it to a PC and kept it charging for about 3 hours when i came back, I switched it on, and it went past the loading bar, till it came to the password bit, i put my password in and it said battery low n shut off, ive done this about 50 times now, it just says battery low, and goes off