When Import or reload world, some big void appear.

Is this only happening on a Bedrock Dedicated Server? What plaform are you using? Are you using any mods?
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Cleaning up old tickets: This ticket had been set to 'Awaiting Response', but has not received a response from the reporter (~3 months+) so is being closed as Incomplete. If you feel this is still a valid issue then please comment, or create a new ticket following the Issue Guidelines which includes steps to reproduce the problem.

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