To assign a TCP/IP port number to the SQL Server Database Engine follow the steps below:
STEP 1: Open the SQL Server Management Studio and login to your Database locally.
STEP 2: Right-click on the server name in the left panel and select Properties.
STEP 3: Select the Connections page on the left side and make sure that “Allow remote connections to this server” option is checked. Then exit SQL Server Management Studio.
STEP 4: Now Open the SQL Server Configuration Manager and expand the node SQL Server Network Configuration. Then Select Protocols for SQLEXPRESS (or whatever the name of your SQL Server instance is). Make sure that TCP/IP protocol is enabled.
STEP 5: Right click on TCP/IP and choose Properties. In the TCP/IP Properties dialog box, click on the IP Addresses tab and scroll down to IPAII section. Make sure TCP Dynamic Ports is blank and that TCP Port is set to 1433 (or whatever you want to set TCP Port).
STEP 6: First Click on Apply button and then the OK button to save your changes. After that restart your SQL Server instance.