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I have a British passport and live in the UK. I was visiting Canada a few weeks ago and crossed the border (by car) to the US and got a 90 day visa.
I am now back in the UK but the visa is still in my passport (it wasn't removed at the border).
On the ESTA application website it says one is not eligible to apply for an ESTA if they are currently in possession of a visitor's visa.
Will I be okay if fly there with my current visa?
EDIT: I should mention, I have a visitor's visa, but this new trip will be for work purposes