migration without consent from client

I called vodacom to find out why my connection was blocked only to find out that my account has a softlock because it exceed the maximum. I was horiffied as I have always selected top-up on all my contracts for this very reason. I was told that in 2013 i migrated to a 2 gig contract with a open line. I dont recall migrating or even consenting to an open line as my initial contract was a top-up. on the 16/03/2015 i logged a complaint. the reference was ref - s3-82g2f-frge8. they claimed that the matter would be investigated and someone will call me back. no one has contacted me with feedback. I followed up on the 25/03/2015. was on the line for 48 minutes and no one was able to assist me in any way. I requested the email address of the CEO and was advised no one a Vodacom has this information. I am digusted by the service and cannot understand how this unprofessionalism can be tolerated.