Unacceptable service from Vodacome to a loyal customer

I have been a customer for over 6 years with multiple contracts with vodacome , however now that I am trying to upgrade to a combo deal I cant because of the 'old system'. No one has a logical explanation to this old system. Being a household brand, glitches like this should be non- existent. This is pathetic service on Vodacoms side since it is such a big brand and no one is able to fix an issue like this. I shall take my business to another service provider capable of completing such simple tasks.