Well, these structures appear to me in minecraft bedrock, the game usually restarts and the structure disappears, but some have remained on the map.

Thank you for your report!
We're actually already tracking this issue under MCPE-55092 so I've requested this report be 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.

Please don't forget to use the search feature before submitting a bug to see if it has already been reported. The less time we spend linking duplicates means more time testing and confirming the bugs.

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