Why am I getting a "XML Validation: Declaration not found for element" when I try to insert into a SQL table with a typed XML field?

I have a SQL table with a XML column defined as follows:

ID  int
FooType nvarchar(255)
FooXML  xml(CONTENT dbo.FooXMLSchemaCollection)

The schema (FooXMLSchemaCollection) is defined as:

<?xml version="1.0" encoding="UTF-8"?>
<xsd:schema xmlns:xsd="http://ift.tt/tphNwY" 
            xmlns:t="http://ift.tt/1uCoKyg" 
            targetNamespace="http://ift.tt/1uCoKyg" 
            elementFormDefault="qualified">
   <xsd:element name="item">
      <xsd:complexType>
         <xsd:complexContent>
            <xsd:restriction base="xsd:anyType">
               <xsd:sequence>
                  <xsd:element name="key">
                     <xsd:complexType>
                        <xsd:complexContent>
                           <xsd:restriction base="xsd:anyType">
                              <xsd:sequence>
                                 <xsd:element name="string" type="xsd:string" />
                              </xsd:sequence>
                           </xsd:restriction>
                        </xsd:complexContent>
                     </xsd:complexType>
                  </xsd:element>
                  <xsd:element name="value">
                     <xsd:complexType>
                        <xsd:complexContent>
                           <xsd:restriction base="xsd:anyType">
                              <xsd:sequence>
                                 <xsd:element name="ArrayOfString">
                                    <xsd:complexType>
                                       <xsd:complexContent>
                                          <xsd:restriction base="xsd:anyType">
                                             <xsd:sequence>
                                                <xsd:element name="string" type="xsd:string" minOccurs="0" maxOccurs="unbounded" />
                                             </xsd:sequence>
                                          </xsd:restriction>
                                       </xsd:complexContent>
                                    </xsd:complexType>
                                 </xsd:element>
                              </xsd:sequence>
                           </xsd:restriction>
                        </xsd:complexContent>
                     </xsd:complexType>
                  </xsd:element>
               </xsd:sequence>
            </xsd:restriction>
         </xsd:complexContent>
      </xsd:complexType>
   </xsd:element>

I'm trying to insert some test data into the table. The XML I'm trying to insert looks like this:

<item>
   <key>
      <string>Attributes</string>
   </key>
   <value>
      <ArrayOfString xmlns:xsi="http://ift.tt/ra1lAU" xmlns:xsd="http://ift.tt/tphNwY">
         <string>fieldName1</string>
         <string>fieldName2</string>
         <string>fieldName3</string>
         <string>fieldName4</string>
         <string>fieldName5</string>
         <string>fieldName6</string>
      </ArrayOfString>
   </value>
</item>}

I'm trying to the following into the database through SSMS:

  INSERT INTO tblLabelInfo
      ([ID] ,[FooType],[FooXML])
  VALUES 
  (1, 'SampleInstance', 
  N'<?xml version="1.0" encoding="utf-16"?><item><key><string>Attributes</string></key><value><ArrayOfString xmlns:xsi="http://ift.tt/ra1lAU" xmlns:xsd="http://ift.tt/tphNwY"><string>fieldName1</string><string>fieldName2</string><string>fieldName3</string><string>fieldName4</string><string>fieldName5</string><string>fieldName6</string></ArrayOfString></value></item>')  

I get the following error message in SSMS:

Msg 6913, Level 16, State 1, Line 1

XML Validation: Declaration not found for element 'item'. Location: /*:item[1]

What am I missing/doing wrong here?

Thanks, JohnB