XML child node without namespace

I have the following xml and child node is without prefix.

<ns1:SearchResponse  xmlns:ns1="alpwsdl.masterPricer" xmlns:xsd="http://ift.tt/tphNwY" xmlns:xsi="http://ift.tt/ra1lAU" > 
<SearchReturn   xsi:type="ns1:searchReply"> 
<searchReference    xsi:type="xsd:int">1234</searchReference> 
</SearchReturn> 
</ns1:SearchResponse>

In my xml schema the prefix is for child node and parent node.

<xsd:schema xmlns:xsd="http://ift.tt/tphNwY"
            xmlns="alpwsdl.masterPricer" targetNamespace="alpwsdl.masterPricer"
            elementFormDefault="qualified">
  <xsd:element name="SearchResponse">
    <xsd:complexType>
      <xsd:sequence>
        <xsd:element name="SearchReturn">
          <xsd:complexType>
            <xsd:sequence>
              <xsd:element name="searchReference">
                <xsd:complexType>
                  <xsd:simpleContent>

How can I fix it?