Hi @VSBTEJA
According to your error message, it is recommended that you could check:
1.The SQL Server Service is up and running.
2.The SQL Server Agent is started.
3.The SQL Server Browser Service is started.
4.The database server is reachable and the SQL server port is opened (1433).
5.The Windows Firewall is Off.
6.The TCP/IP network configuration for the SQL Server instance is enabled.
For more information, you could refer to:
https://spgeeks.devoworx.com/cannot-connect-database-master-sql-server-sharepoint-configuration-wizard/
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