Package delayed and no reply from Customer Contact Centre

I ordered an item online and it was shipped from China. It took less than a week to get from China to South Africa, and has been sitting at the sorting centre since the end of April.

I have sent emails starting in mid-May to the Post Office's customer query/contact centre but despite being promised to have someone contact me within 48 hours, I still have had no contact.

I would like to have an update of when my package will finally be released from the sorting centre as this lack of correspondence is extremely disappointing and frustrating.