creating chart using element

Hi,

I have followed below steps to create pie chart using elements but it is showing greyed out Bar chart instead of Pie

1) created blank document

2) added dataprovider

3) added query specification

4 saved document

5) refresh document

6) got elements specification using GET from existing manually created pie chart report , those specifications are attached

7) Below mentioned are elements specifications I used except header, body and footer in request body with POST method in order to create pie chart,

I mentioned below specifications one by one and finally saved document using PUT,

<element type="Cell">

        <id>4</id>

        <reference>UIREF:V=1:RID=1:BID=4</reference>

        <parentId>2</parentId>

        <size autofitHeight="true" autofitWidth="false" minimalHeight="1548" minimalWidth="15048"/>

        <position verticalAnchorType="None" horizontalAnchorType="None" y="432" x="7416"/>

        <padding bottom="156" top="156" right="213" left="213"/>

    </element>

element type="Visualization">

        <id>11</id>

        <reference>UIREF:V=1:RID=1:BID=11</reference>

        <name>Block 1</name>

        <parentId>2</parentId>

        <size minimalHeight="11250" minimalWidth="15000"/>

        <position verticalAnchorId="4" verticalAnchorType="End" horizontalAnchorType="None" y="900" x="450"/>

    </element>