Taxes problem

Hello,

I have a big problem with prices and TVA.

I have a website https://nfbsante.com. It’s a French website, and for French version, no problem.

But i use “Prices and Currencies by Country Module Options” for display prices in CHF for Switzerland customers (i use a VPN for display prices like a Swiss).
In my backoffice, i put price without Taxes and after i applied taxes of 2.5%.

But the calcul on the taxes have a problem for CHF
Exemple with this product : https://nfbsante.com/boutique/barre-caramel-cacahouette/
> Price in my backoffice without taxes = 24,39
> Taxes of 2,5% = 0,60
> Good price is 24,99
> Price display on website : 24,60 = PROBLEM

Price of taxe display on my checkout : 0,60 (good)

I try to change the price of the product without coma.
For exemple 25 CHF for replace 24,39.
= NO PROBLEM

After i try with an another price with coma, for exemple 25,xx
= PROBLEM

What is it? a bug ???
Can you help me pls

Screenshot : https://transfernow.net/810bu5z5w42e

Thank you

Mickael

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