Queries Disappeared for no reason

Hi Jie09 ,
According to your description, your query disappeared or reverted to its initial state without any apparent reason. You can troubleshoot this by doing the following:
First, if you are working in Power BI or Data Factory, there may be a version history that applies to the workspace. This can allow you to revert to a previous version where the query still exists.
Second, if the query is part of a data stream in Gen1, you can try migrating him to Gen2.
Finally, you can also utilize the Query Activity feature to view all running and historical T-SQL queries. This may give you insight into any long-running or frequently-running queries that may be affecting your workspace.
You can refer to the following information for more details
Move queries from Dataflow Gen1 to Dataflow Gen2 - Microsoft Fabric | Microsoft Learn
Access the Power BI activity log - Power BI | Microsoft Learn

Best regards,
Albert He

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