Hi @Joann Liao ,
According to your screenshot, did you connect to default instance(MSSQLSERVER) in SSMS? The default instance is SQL 2017 now, but it is still showing SQL 2014 version in SSMS.
SSMS Object Explorer Showing Blue Question Mark for SQL Server default instance, this means that SSMS does not know if the service is running or not, by way of a WMI call. Make sure SQL server instance is running, check this from SSCM. Please close the SSMS, run the SSMS as administrator, then connect to default instance. A white arrow on a green circle icon is the correct state for SQL server instance. If this is still not work, try the suggestion from this thread.
After connect to SQL server, please using select @@version to check SQL server version.
By the way, we can also get the SQL server version from error log as below screenshot.
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