Hi Anil,
It looks like we have run into this once or twice in the past where the post upgrade is trying to point the sequence to an already occupied value. The solution that I'm seeing for this is to comment out the lines of Javascript below in the postupgrade.xml. This is a bug in the script that will be addressed in future releases (R&D reference is NEO-47335).
<!-- <javaScript label="Reset nmsTrackingUrlId sequence">
.....
sqlExec("alter sequence NmsTrackingUrlId restart start with " + nextStart + ";");
....
</javaScript>-->