The currentValue field as returned by Dynamic Management View sys.dm_db_tuning_recommendations is stuck in the "Verifying" state when Automatic Tuning does its first verification for FORCE_LAST_GOOD_PLAN.
This fix is included in Cumulative Update 1 for SQL Server 2017.
About SQL Server 2017 builds
Each new build for SQL Server 2017 contains all the hotfixes and security fixes that were in the previous build. We recommend that you install the latest build for SQL Server 2017.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
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