on Just Publishing Advice:
Many new UK self-published authors I have had reason to be in contact with are often unaware that their ebooks that are available on Amazon.co.uk are restricted to UK buyers only.
Depending on where you live, Amazon’s geo-control of its Kindle stores can restrict what you can buy.
This is logical for physical products that need to be shipped by online retailers. But for electronic downloads such as ebooks, it is not always logical.
In many cases, you can buy ebooks from other Amazon stores. But it is not always the case.