I have the same issue as the bug report below; every time I try to upload a world to my realm It goes through 100% completion and then gives me a generic error. I see that this has been ongoing for over a month now, and if it can't be rectified soon I would appreciate a refund for the realm I purchased.
https://bugs.mojang.com/browse/REALMS-474?jql=text%20~%20%22cannot%20upload%20world%20to%20realm%22
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Thank you for your report!
We're tracking this issue in REALMS-474, so this ticket is being resolved and linked as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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