Several problems (Location, Checkout, Stability Errors)

Hi,
We are trying to achieve product presentation in multiple currencies and checkout in GBP, USD and EURO. However, we are facing an error when we try to checkout from an EU location and also the checkout is defaulting to GBP. Moreover, after the checkout the currency switches to GBP until we change it again. I attached this video to demonstrate this issue. https://www.loom.com/share/8ce72b02bdc94ad79dd98cf6dcb84eca
My guess is there are some stability issues causing this problem. Can you please suggest a solution or investigate on this. Please inform me if you need anything else.
Regards,
Gounay