When I was going to enter to play minecraft java edition appeared to play in the demo, I found it strange and I've been trying and trying so far not having success, and yes I already bought minecraft java edition.
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Thank you for your report!
We're tracking this issue in MCL-16570, so this ticket is being resolved and linked as a duplicate.
That ticket has already been resolved as invalid, which means this is a technical support issue. Please take a look at the parent ticket (MCL-16570) and see if a solution is provided there.
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DuplicatesΒ MCL-16570 Read the Moderator note in that link.