Urgent attention from Vodacom side

Bad service from Vodacom, today I went to vodacom in Craighall Johannesburg.. I went there to try upgrade my contract and they told me that my contract was downgraded without any permission from me, they asked me if I had missed any payments and I know all my payments are up to date. I was told that they will phone me during the course of the day, but that still does not tell me why they decided to downgrade my package. I found this very unacceptable, I want an answer now from Vodacom