Phone charger has not worked properly since I bought it. Sometimes it makes a continuous ping sound, does not charge over 78%, tried different outlets, tried charging other peoples phones, NOTHING WORKS PROPERLY !!! Bought it last May at US Cellular store, they will not do anything to help me! Have been complaining since I bought it, Paid $50 for it and no one is helping me! Tried 3 different phone numbers to DDo