False advertising for 2020 app

I received a promo advert to purchase the entertainer app for the new year 2020 for R295 - a promo they were running for a short period. I purchased the app, but when I wanted to use it recently my deals were locked. I contacted customer service and they informed me that I purchased the 2019 app however I have proof the "congratulated" on purchasing Entertainer 2020. They told me to purchase the app for 2020 at full price and they will refund me what I paid last year. I demand that I get my product for the new year at the price I paid as this is false advertising