Mtn business contracts just for certain people?

Last week my dad wanted to upgrade his contract which its due for an upgrade. He selected the new contract sim only deal 23gb 1000min contract for R579 mtn made for business L. The criteria is 3months bank statements,business letterhead, id,sars registration of business. No a week later his contract was rejected, because he dont have a business account, he has an private check account.On the paper the criteria is bank account and a minumum income of R3500 which was met. Would like to know