MTN won't let me pay them.

When I moved my bank to FNB, it took me 7 months to move my debit order. 7 months of going in store on a monthly basis, receiving sms' that my account has not been paid. eventually it got sorted. Now, I moved to Discovery only to go through the same thing again. 6 months down the line and I cannot pay my MTN account. Apparently Discovery is not a Debicheck patner and it is impossible to bank with Discovery and pay my MTN account by debit order. All this when several people have assured me they bank with Discovery and pay their MTN accounts via debit orer. Discovery also assures me it works. I am at a loss - MTN don't want me to pay them. Every month it is the same story, it is getting tiring. I AM TIRED OF MTN. Wouldn't it be in MTN's bet interest to ensure people can pay them form all major South African banks?