Registered post going into black hole

Please can someone tell me how a registered letter can take more than a week to go from Dundee to Isando and it is still not there? It has been in JHBNET since 15 April..... Are you on strike again?<br> <br> TRACKING<br> LINE TYPE DATE TIME BRANCH COMMENTS <br> 1 In Transit 2015/04/15 01:32 JHBNET C*** <br> 2 In Transit 2015/04/15 01:01 JHBNET C*** <br> 3 In Transit 2015/04/13 18:20 LDY C*** <br> 4 Item accepted by branch 2015/04/11 23:13 TALANA POSTOFFICE ACCEPTANCE (O) SCAN <br>