old prices still shown

I installed your fantastic plugin and I tested many promotions. But in the meantime I’ve noticed some problems with checkout page so I switch off all plugins. And then I observed that in incognito mode (or after deleting browser cache) I still see the old prices of some products – I changed the prices a few days ago. In the configuration of the product are shown the new prices. And the prices change to actual after adding the product to the basket. So I deactivated all plugins, even change my theme to twenty twenty, even copy one the product using Duplicate post plugin but the problems still exists. And the new, copied product has shown at first the old price!!!
What should I do to cancel the old prices?
Here are examples of products with the problem:
https://krainaaloesu-forever.pl/produkt/miazsz-aloesowy-do-picia-aloe-vera-gel-naturalny-1litr/
and the new copied product with the same problem:
https://krainaaloesu-forever.pl/produkt/aloes-997-do-picia-naturalny-aloe-vera-gel-1-litr-kopia/
The normal price set in configuration is 118,15 z? (no promotion) but in incognito mode you can see 96,06 z? (the old price).
Do you have any idea how to resolve the problem?

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