I bought the game and downloaded it, but it says that I don't own it. I've tried deleting it and redownloading it but that still doesn't work. I'm not really sure what to do.
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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.
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Please refer to this article: https://help.minecraft.net/hc/en-us/articles/360029643892-Can-only-play-Minecraft-demo-Java-Edition-
If that does not help, please contact Mojang Support.
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📓 Project Summary – ✍️ Feedback and Suggestions – 📖 Game Wiki