Unavoidable adverts with airtime top ups

This is a repeat complaint. About two weeks ago I posted complaining about the fact that every time I purchased airtime, MTN would send me at least 4 SMSes advertising various other data bundles etc. In response to that complaint, I received an apology message and a message saying that my number had been removed from all marketing services. Yet, nothing has changed and I still receive just as many annoying spam messages with every purchase. If you had no intention of fixing the problem, rather don't lie to your customers.