Cancellation of MTN SimCards

For the second time in three months, MTN SA cancelled my sim card (I use Afrihost as service provider) for no reason. I logged a call with Afrihost, to find out that my sim card was cancelled by MTN, as I apparently have a contract with MTN? I have had the same Vodacom number for 9 years, I AM NOT AN MTN Customer, yet, that is the reason for the cancellation of my sim card?

Only way to fix it? For the third time, I have to go to an MTN Store, PAY for a new sim card and wait for Afrihost to connect it. There is no way to phone MTN, get any form of assistance. I am beyond disgusted.