Have credit on account but DSTV suspended service

When I purchased and activated my DSTV i activated the Explora telephonically, the next day i phoned and asked to link a HD decoder as extra view. Monthly payments went off normally then the extra view stopped working I phoned and they said it was not paid I checked my statements the debit order for the Explora went off but the bank eventually canceled the 2nd decoder charge as a duplicate. In the beginning the HD decoder was set up as extra view but for some reason multi choice started billing me for 2 subscriptions, DSTV credited my account for the extra decoder double bill. My statements from DSTV show for the past 3 months i have still credit available, but dstv disconnected all my services and stated that i owe them money, i have phoned numerous times to resolve this and they promise it will get sorted but nobody phones me back.and when i speak tho them they make me feel like a layman. So now i want to cancel my account delete all my data as i will never ever again use DSTV i would also like a refund of my credit on my account..