Spam sms's disturb my sleep at 4 in the morning

I wish to make a complaint against MTN. As I previously mentioned in an earlier complaint. on the 2nd of November 2015. This happened again yesterday at 04:46 am and today again at 04:47. Spam messages which are themselves a blight that both Vodacom and particular MTN seem to lay upon their customers should never be sent at this time disturbing their customers sleep just to market themselves. It is completely unacceptable and it is actually a form of harassment. MTN should immediately adjust their system as there is no viable reason that this spam must be endured by their customers. Failure of MTN to rectify this immediately, will see me drop them like a hot potato. This is a total disgrace on their part.