Hi Nidhi,
In your first post you mentioned routing of 810 & 852 messages but your conditional routing is based on ANSI X12 message 850 version 4010. If you want to route other types of messages based on only ISA ID field then you have to adjust your XPath expression to something like:
Xpath.//S_ISA/D_I06 (this will ignore the value of the root node)
Regards,
Ryan Crosby