Serial key is different in master and slave machine

Hi,

I am usinf Slony slony-I-2.0.2 in windows. I have a Master and a slave
machine. When the master machine is failed, I have executed the failover
script and the slave is switched to master. My problem is that while
inserting a record into the current master machine, it will show an
error saying that Duplicate key value. Please help me to overcome this
error
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