Fixed price issue

I’m facing an issue with fixed pricing on my website. When I set a fixed price for a product, it displays correctly on the product page, but at checkout, it gets converted based on the store’s main currency instead of using the fixed amount. For example, if a product is set to TTD 20 and the fixed USD price is $1, the checkout still converts the USD price instead of keeping it at the fixed price. Due to this issue, I had to deactivate the plugin and set my store to use only one currency. So currently, the fixed and regular prices appear the same in TTD.