Question about Noctua Nf-S12a Pwm

Dear digitec team, A short time ago (10 min ago, on 14.11), the price comparison showed the price of 19.50 CHF (still visible in the price comparison). Underneath it said: Selected offer price: 26.60 CHF. When I wanted to buy three fans at the tempting 19.50 CHF, it only showed me the 26.60 CHF in the shopping basket, but this price was only set today (15.11). I tried various things (reloading the website, choosing a different supplier, choosing a different coloured product, etc.), but I never got the price of 19.50 CHF. I think that's pretty stupid, to put it nicely. If you don't believe me, luckily I took a screenshot before midnight. Can you please explain to me why you didn't want to sell me the fans at the daily price, but only allow me the subsequent price? I would have liked to buy the fans, but now I find them very expensive. A surcharge of 7.10 CHF per fan makes a whole fan out of three fans! Thank you very much for your answer, kind regards