@xiongNWN-8368 Welcome to Microsoft Q&A, Thank you for posting your query!
Firstly, apologies for the delay in responding here and any inconvenience this issue may have caused. This article lists troubleshooting techniques to use when you can't connect to an instance of the SQL Server Database Engine on a single server.
If the issue still persist, please share the screenshot of the error message. I would like to work closer on this issue
Hope this helps!
Kindly let us know if the above helps or you need further assistance on this issue.
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