@atharabbas
I am not IT expert, and its pretty confusing. Your problem is justified.
So, I am responding here so other related field guys may also contribute
In my opinion, the main difference between the 2 NOC (2171 & 2173) is that if your work is more related to interaction and understanding clients requirements before the implementation its 2171
If its more related to interaction and understanding of the programming team then its 2173.
Your duties relate more to 2171 (as i understand) but my suggestion is consult some expert, either someone who applied in 2013 or some senior IT expert (take print out of both NOC's and your experience letter).
Moreover, i think your experience letter needs to be reworded. Try to make it little concise and to the point. You need not to mention all your duties, just the ones which are related to your primary NOC and then add max 1 or 2 to show that you have bigger role.
atharabbas said:
Thank you to clarify dear. I have send you PM (inbox).