Incompetence continues at DHL

It seems that DHL just cannot get it right. Following my last complaint about my parcel not being picked up I was promised a call...none came, rather a delayed email stating that they made a mistake and thought that the delivery address was the pick up address and then continued to ask me to pay more money into their bank account for an amount less that what was transferred originally. I'm not sure if DHL even realise their own height of incompetence. Now they owe us a refund for the balance but have not responded to emails since last week. Is there any management or leadership in this organisation?