Rollback Transaction in wso2esb 4.7.0 - postgresql

Question

I'm using wso2esb 4.7.0 and postgresql and inserting values in two different tables of same database through proxy service.This insertion operation in working properly.Now my scenario is if my second insertion fails,first insertion should rollback.for that i have use transaction mediator(rollback transaction) but it is not working properly.
proxy configuration and fault sequence as follows:
<target >
<inSequence onError="myFaultHandler">
<transaction action="new"/>
<dbreport>
<connection>
<pool>
<password>Youtility11</password>
<user>youtilitydba</user>
<url>jdbx:postgresql://localhost:5432/DB2</url>
<driver>org.postgresql.Driver</driver>
</pool>
</connection>
<statement>
<sql>
insert into table1(name,id) values(?,?)</sql>
<parameter xmlns:ns="http://org.apache.synapse/xsd"
expression="//name/text()"
type="VARCHAR"/>
<parameter xmlns:ns="http://org.apache.synapse/xsd"
expression="//id/text()"
type="VARCHAR"/>
</statement>
</dbreport>
<log level="full">
<property name="name" expression="get-property('name')"/>
<property name="id" expression="get-property('id')"/>
</log>
<log level="full">
<property name="text" value="Reporting to the DB2"/>
</log>
<dbreport>
<connection>
<pool>
<password>Youtility11</password>
<user>youtilitydba</user>
<url>jdbx:postgresql://localhost:5432/DB2</url>
<driver>org.postgresql.Driver</driver>
</pool>
</connection>
<statement>
<sql>
insert into table2(firstname,lastname) values(?,?)</sql>
<parameter xmlns:ns="http://org.apache.synapse/xsd"
expression="//firstname/text()"
type="VARCHAR"/>
<parameter xmlns:ns="http://org.apache.synapse/xsd"
expression="//lastname/text()"
type="VARCHAR"/>
</statement>
</dbreport>
</inSequence>
</target>
and sequence is:
<sequence xmlns="http://ws.apache.org/ns/synapse" name="myFaultHandler">
<log level="full">
<property name="message" value="**ROLLBACK**"/>
</log>
<transaction action="rollback"/>
</sequence>
here when i'm inserting wrong record in second table it shows error but first table insertion is done.why rollback is not working? let me know..
thanks in advance