TV Error Code 16-4

I changed my DStv package in January 2015 and ever since the change I continue receiving error code 16-4. When switching on the TV the error code appears and will not clear until telephoning the Help Desk who obviously do something to rectify and get the picture started. Each time I speak to a different person and given different instructions what to do, but to no avail. During programmes the same error appears now and then. I wrote to MultiChoice and was told the matter was resolved and that when the package was changed my HD decoder had not been activated. This was apparently done but the error still appears! The error refers to account possibly being in arrears. This is ******* as my account is up to date and MultiChoice charge me monthly by debit order. One pays enough for TV without this frustration. Also the consumer is having to pay for telephone/cell costs just to watch TV when it is Multichoice's problem. I believe for all the inconvenience and costs MultiChoice should be made to refund the customer! Perhaps the Watchdog needs to look into this and the workings of MultiChoice.