try to check the .htaccess file in the root directory.
You will need to check httpd.conf file and check the entry for the domain name. Confirm the server IP address for the domain name. Restart Httpd server once the changes are been made.
This can also be cause by DNS cache being not released on the computer.
Have you tried using different DNS servers besides your ISP DNS like google and so on.
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Check the IP of the domain in dns zone file and httpd.conf are same, if not change the IP in httpd.cnf with the one in dns zone. If both are correct, then check the to which IP the site is resolving to, use dig command to do this and check the apache conf has the same IP for its virtual host.