Main account holder cannot buy data anymore ***!!

All of a sudden I am unable to purchase data from MyVodacom! I get the following message: Unfortunately you are not the main account holder and can only buy bundles using a bank card or credit card. Please contact the main account holder to give you permissions or contact Vodacom customer care if you are in fact the main account holder. I have had this account with this number for more than 10 years! Nothing has changed. NB!!!! *** Vodacom! I really don't appreciate the discomfort!