I made a sale for 3 games at 50% where customers can pay $12,50 for all of the games as a bundle instead of $15,00 which would be the total price. But it seems like the individual games aren't on sale? Did i do something wrong, or is this a bug? here is the link to the sale https://itch.io/s/102817/mid-september-sale

I checked and there are bundles where the individual games are on sale and there is a bundle pricing. So you can either buy the bundle or individual games. But those bundles I looked at had no additional discount for purchasing the whole bundle, like you wanted to offer and what I would expect for buying a whole bundle instead of only what I am interested in from the bundle.

So it seems to me, that your pricing is the good one and the other ones are bugged or problematic advertising. (And of course that your individual items do not have the discount looks like a bug. You see the discount tag on the game name in the bundle, but not on the game page..

Like really, now that I think about it, what exactly is the benefit of a bundle, if the sum of the parts is exactly the sum of the parts? And that is what I saw on those bundles. I know discount bundles on steam and those are reduced price tags and additional reduction if you buy all the stuff together.

Also viable would be a discount only applying to the whole bundle, but no discount to the items. But if you accidentally would have activated this option, the discount % would be wrong.