How do I combine the display of a map with With ItemValue

Hello everybody,
I’m using the following code in an HTML file. This is saved in the openHAB “HTML” directory and is displayed in an openHAB Habpanel via the “Frame” widget. Everything works fine up to here. Unfortunately I have not yet managed to display the values with the fields “{{itemValue (‘TankShellBlitzE5’)}}” and “{{itemValue (‘TankAralStationOpen’)}}”. Since I’m actually still a beginner, I need the help of experts.

Best regard

<!DOCTYPE html>
Leaflet Map
<style>
    .container{
        height: 900px;
        width: 100%;
    }
    #map {
        height: 100%;
        width: 600px;
        display: inline-block;
    }

    #button-container {
        width: 20%;
        height: 100%;
        display: inline-block;
        vertical-align: top;
    }

    button {
        height: 67px;
        width: 185px;
        border-color: #00FFFF;
        background-color: #000000;
        color: cyan;
    }

    th, td {
        border: 2px ridge cyan;
    }
    td{
        width: 23.88px;
    }
</style>
    <table>

        <tr id="Total">
            <td >Preis: {{itemValue('TankShellBlitzE5')}} €</td>
            <td style="height: 67px; width: 67px"><img src="/static/bilder/aral-1.svg" alt="Aral"
                                                       style="width:40%"></img></td>
            <td >Sorte E5</td>
            <td >Aral ist: {{itemValue('TankAralStationOpen')}}</td>
            <td class="customText" ></td>
            <td class="customBtn" ></td>
        </tr>
    </table>
</div>