HELP!!! Sony Ericsson Z750a problem...?

so everytime i plug my charger into my sony ericsson the screen flashes and says optimized charging and then goes out it just flashes the screen hasnt turned white or anything ... it stays on just wont charger for some reason and i had it plugged in for 2 hours and nothing .. is it complete dead? or is there a fix? someone please let me know ive taken the battery out and cleaned the connecters but still nothing i dont know whats wrong with it but theres about 10% battery life left on it so i dont wanna turn it on and off so its been off since this morning anyone have this problem before? i have 2 different chargers and it does the same thing ....