openlayers 2 - How to Update Multiple Fields of one Layer Using WFS Service

Trying to update two fields of a shapefile using a WFS update service published from GeoServer 2.4.3 with OpenLayers 2.13.1. I have a JavaScript with all the OpenLayers fun and a HTML document with all the interface fun. Essentially the user clicks on an object and updates a form and then saves it.

Assuming its possible? It's probably really simple but I can't crack it. The fields do not update and in the demo requests the service times out.

Here is the code I am trying;

function saveHandler() {
newDim = document.getElementById("dimension").value;
var num = parseFloat(newDim);
var newDimRound = num.toFixed(3);
newMaterial = document.getElementById("MaterialDD").value;

var saveDetails = OpenLayers.Request.POST({

        url: '',
        username: '',
        password: '',
        data: '                        'xmlns:topp="http://www.openplans.org/topp"\n' +
                        'xmlns:ogc="http://www.opengis.net/ogc"\n' +
                        'xmlns:wfs="http://www.opengis.net/wfs">\n' +
                        '\n' +
                        '\n' +
                        'Field 1\n' +

                        '' + newDimRound + '\n' +
                        'Field 2\n' +
                        '' + newMaterial + '\n' +
                        '\n' +
                        '\n' +
                        'Spatial_ID\n' +
                        '' + getSpatial_ID + '\n' +
                        '\n' +
                        '\n' +
                        '\n',

        callback: handler
    }); // end of Post

    function handler(updateSQL) {
        alert("Details Saved!")
    } // end handler    
};

I have tried putting the fields in their own property sections and different orders to no avail.

Answer

Worked it out, feel like a dunce! I needed to separate each property into it's own distinct property within the xml, rather than combine it into one.

I had:

Needed to have:

Like so:

        data: '                        'xmlns:topp="http://www.openplans.org/topp"\n' +
                        'xmlns:ogc="http://www.opengis.net/ogc"\n' +
                        'xmlns:wfs="http://www.opengis.net/wfs">\n' +
                        '\n' +
                        '\n' +
                        'Field 1\n' +
                        '' + newDimRound + '\n' +
                        '\n' +

                        '\n' +
                        'Field 2\n' +
                        '' + newMaterial + '\n' +
                        '\n' +
                        '\n' +
                        'Field 3\n' +
                        '' + remarks + '\n' +
                        '\n' +
                        '\n' +
                        'Spatial_ID\n' +

                        '' + getSpatial_ID + '\n' +
                        '\n' +
                        '\n' +
                        '\n',