When I make any purchase on the Marketplace, it tells me “Sorry, we are unable to complete your purchase. Maybe check your internet connection?” And my internet is working perfectly fine.

Thank you for your report!
However, unfortunately we are unable to help with your report.

As this is an issue with your account or billing, you will need to contact Mojang Customer Support directly.

The bug report site is manned by volunteers and we don't have the ability to assist.

Best of luck getting it sorted.

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