I bought a minecraft, but only the demo version comes up.
I've been sure of your ID.
I've made inquiries, but I can't reply.
Linked issues
Comments

I tried to contact them, but they didn't help me.
I want to know how to get a refund.
Hey there!
This appears to be an account / payment related issue and the bug tracker does not have the appropriate resources to help you with this problem. In order to receive assistance, please contact Mojang Support, regarding your concern.

Thank you for your report!
We're tracking this issue in MCL-16570, so this ticket is being resolved and linked as a duplicate.
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Hmm, I think this might be a technical support issue, maybe try contacting them, they should be able to help you