Problem with products on sale

Hi, I have a product on sale and at first see the original price that is strikethrough that after 2 seconds gets changed to the sale price! e.g. check the product I attach, original price, 12,83 gets chagned to 11,55, which is the sale price! So customer sees the -10% sign but it’s like I mock them and give them no price at all!

It’s the booster plugin that is causing it. I deactivated it and it works as it should. Any idea how to fix this bug?

Thanks

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