Fedex does not communicate

Our shipment took 4 days from China and arrived at Fedex in Johannesburg. It is now 2 weeks later and all they can tell me is it is at customs. They cannot communicate anything about how they will get it cleared nor what is the reason for the delay. I have sent them every document they could possibly need. Maybe it was lost or ******, but no information is provided. I send emails daily asking for an update and no one has the courtesy to reply.