Currency Switcher not switch

We have Czech and English languages on the website. When we switch to the English language, the price does not change to usd. It used to work and suddenly it doesn’t. So I don’t see what we are doing wrong. I also turned off the cache plugin Wp fastest Cache. https://tinyurl.com/27lnapaq

Can you help us?

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