Unable to buy endwalker (internal error)

As the title mentions - I am trying to pre-order endwalker via https://store.eu.square-enix-games.com/
Upon verifying my payment info, this message appears: Please wait while your payment information is verified by our banking services. This may take up to 1 minute.
They then give me an error message that reads "An internal error has occured. Please try again in a few minutes"
Every time i have tried my hardest to give square enix my money - they simply will not accept it. I have tried multiple times over many days to purchase endwalker.
I am from Australia if this is relevant.
Any insight would be helpful. I have a support ticket pending but i hear SE is busy these days with all these new players

I tried once again 24 hours after my initial post and support ticket submission - with no word from customer support and no replies in this thread, it now works.
I am now in posession of the Endwalker expansion. I have no idea what changed between previous attempts to purchase, and todays attempt.
The only thing i did differently was provide my personal phone number in the required fields in the payment menu with my full area code included instead of how we, in Australia normally provide each other our contact numbers.
Perhaps this is what was tripping the online store?... Who knows...

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As the issue has been resolved, this thread will be moved to Closed Concerns.

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