Bad service from the Post Office

I ordered an item from overseas. The package was first scanned at the post office on 2018-08-12 although the international tracking number showed that the package arrived in South Africa mid July. The package is at customs since 2018-08-17. I have send the invoice for the goods to customs to speed up the release of the package. I have been waiting for it for almost 3 months now. When will it be released? Tracking number RI ********** 58ZA I will never use them again.