The most common reason for missing "Price reduction" discounts on some discount campaign products after a while is price updates from outside the app.
Since the app changes actual prices, price changes from outside the app may overwrite discounts (sale prices) from the app. This may be due to price import, another app or tool that also updates prices (e.g. dropshipping or inventory management tools).
The app only changes prices during activation, deactivation, or refresh processes, but not in the background, and does not automatically apply discounts to products with updated prices.
We recommend that you update prices when there are no active app discount campaigns. You can deactivate your campaigns for a while, update your product prices, and then activate the campaigns again.
You can get back the app discounts (sale prices) that have been erased by price updates from outside by reactivating your discount campaigns (deactivate and activate again). However, all price changes that occurred during active discount campaigns will be ignored.