From Netsight Console, if it's supported in that version (I do not have it installed anymore).
Click on IP address in All Devices Folder, or any folder.
Select and highlight, Double click on unit. in middle bar you will see something like this.
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Once you change these values around, by clicking on the appropriate column,
Hit the arrow and bang ! button.
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This should set the sysLocation and sysContact MIB variables.
Let me know if this works and helps.