D865 Action URL Incoming Call - No output on screen

Hello together,

up to now we have been using devices of the 760/720 series. There, a script is called via ActionURL on an incoming call that identifies the customer and sends the name as a response back to the phone (according to the corresponding instructions). This answer (XML) was then displayed on the phones' screens.

Now we have currently purchased a few D865, and there also specified the URL. The call also goes to the server (visible in the server log), but the response is not displayed on the phone.

The output of the server looks something like this (already adjusted) :

echo '<?xml version="1.0" encoding="UTF-8"?>';
echo '<IPPhoneBatch xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../schemas/minibrowser.xsd">';
echo '<IPPhoneText dtmf="off" id="play_ringtone" state="relevant" stop_auto_leave="true">';
echo '<Title>Anruf ' . $callerid . '</Title>';
echo '<Text>' . $text . '</Text>';
echo '</IPPhoneText>';
echo '</IPPhoneBatch>';

Can anyone help ? Why is the output not displayed on the D865 ?

Thanks + greetings,

André