Hi @Emon_Hosen 
Welcome to the Kinsta Community!
It’s possible that Localwp and DevKinsta are using the same port, which could be causing a conflict. Please stop the site that is running in Localwp and ensure that Localwp application is closed and not running.
Next, in DevKinsta, navigate to Settings >> Port Selector, uncheck “Auto-detect ports,” and set port 80 for HTTP and 443 for HTTPS. After making these changes, check your site again to see if it resolves the issue.
Let me know how it goes! 