Product price error in different currency

Hello,

We have two problems.
1.
Product prices default currency TL. When we change the EUR or USD currency on the products, the discounted price is correct, but it shows the TL price of the product as the normal price.

I am sharing the screenshot:
1. Prices loaded in the system
2. TL prices
3. Price in EUR. ( Should be 479.9 /379.9)

2.
The other problem is that the Multi Currency plugin slows down the admin panel and the site.

Thanks
Zeynep