Hi, Shahgols,
Welcome to Sony Community!
Did you install or update a software before this started? Were there any changes in the settings? Check if the wireless network driver is installed in Device Manager. If the wireless adapter is not properly installed, has an exclamation point or and "X" mark then this is a possible driver issue. Try to reinstall it. Right-click the driver > select Uninstall (DO NOT DELETE) > Restart the computer. The driver should be reinstalled. Test wireless network.
Regards,
Vincent
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