Option 1: Check Your File Permissions
Inside public_html>>
folder should have a setting of 755 
file should have a setting of 644
and then check if it works
Option 2: .htaccess File
Right-click on the .htaccess file to .htaccess_old 
and then check if it works
Option 3: Deactivate/Reactivate Your Plugins
and then check if it works