Vodacom disappointment

I was notified by Vodacom that I am due for an upgrade. The package that I want, includes R185 airtime with a Samsung A34 it will cost me more or less R390. With my current package I get +-R220 airtime I currently pay R290. After numerous attempts to upgrade, I was advised by the upgrade/sales specialist the Vodacom system does not allow for a shift to a lower package airtime even though Vodacom will receive a R100 more from me on a monthly basis. Vodacom can only offer me a R500-R600 contract but not the contract for R390 that I want. My experience with the company does not correlate with their slogan "further together...", we will be further apart! I've been with Vodacom for almost 15 years and it was advised that I should take out a new contract in order for me to get my preferred package. Makes no sense and is disappointing!