I have recently purchased a realm on the Nintendo Switch Version of Minecraft. But whenever I try to upload an existing world to that realm through the "replace world" button, I get an error message and a pop up notifying me that the level export has failed. I tried to restart both the app and the machine itself to no avail.
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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.
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