False promises

I have insured my vehicle with Discovery insurance. And recently I received a comparative quote from another company offering vehicle insurance; the quote was significantly lower than what Discovery was currently charging me. I called Discovery to find out if they can match this new offer and the retention agent I spoke to ran some calculations and gave me an offer a bit closer to what the other company offered. She continued to send me the new revised policy schedule and told me that the new amount would be debited from the 25th of January already.

This was not the case at all; I was billed the same amount as I was the previous month and this was contrary to what she said and what the new policy schedule contained. I want to get clarity on this and on why I was promised something that did not happen.