Non-existing Service from MTN

We have a big problem with our MTN prepaid sim - it stopped sending international SMS's. Been using it for more than a year in a modem. We tried 4 other new prepaid sims last night, same thing, doesn't send international SMS's. We can call to international numbers though but no SMS's. <br> <br> We've been calling MTN's prepaid customer help line but you don't get to talk with any representative. The service is just non existent with this company. It seems like the moment people start making good money in this country their service level drops by the day or maybe it's just to be blamed to *********** management. People just don't have any proud anymore in their work and what they stand for. Again, once they make the money, why should they worry about a small business' complaint - doesn't affect them.