PAYING FOR SNAIL SERVICE

In July 2021, I took up a subscription with service provider MWEB and signed for FIBRE @ R499 - 25MBPS Download and upload. I recently had a look at my package on my web profile only to see that i have been billed for 25/10. When i called MWEB yesterday they said to me that a correspondence was sent out last year in September 2022 changing the speed to 25/10. I then searched my emails and found nothing, so i suggested to the service agent please forward the same email. He has not done so. Without my approval i was downgraded and i have been paying for the full subscription. MWEB you are behaving like the politicians of this country roguish. I want a full refund....