Why does currency change at checkout in my online store?

[perrosucio]

Hello, in my store I can receive payments from the US and Canada, when you access the store from the US it will automatically change the currency to US dollars, but when you proceed to make the purchase at the checkout the currency changes again to Canadian dollars. I don't know why the currency doesn't stay the same until the end of the transaction, if someone could help me with that I would appreciate it. 

[Holland1121]

I also have this same question and I cannot find any proper answers on the internet and also need a solution. Works like a charm!

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[pipliz96]

Did you find a solution because I have the same problem and can't find help. Thank you Lisa