ERROR 143-0 issue

We currently have three decoders (2 Xplora's & HD Decoder DSD4137) which were installed by an approved DSTV installer. We constantly have issues with the HD Decoder DSD4137 as it always displays 143-0 error, this error occurs around 9pm then it does not play anymore.

- Installer has checked the connection more than 5 times & can not find a fault - I've spent more than two weeks trying to get assistance from Multi choice call centre but unplugging the decoder can not be the answer to this issue - Read multiple threads and there's no real solution to this item How can this be resolved? as I can't even get put through to any specialist to assist me with this issue. This is very frustrating and the service is appalling for the amount we pay we expect decent service at least.