You have set up www to non-www redirection. Therefore if someone visits www.centrecsai.org they are redirected to centrecsai.org (WITHOUT www) with a search engine friendly 301 PERMANENT REDIRECTION.
When they visit centrecsai.org (WITHOUT www) of course they are NOT redirected anywhere.
It would be entirely stupid redirecting centrecsai.org to www.centrecsai.org because visiting www.centrecsai.org would redirect back to centrecsai.org. But centrecsai.org would redirect to www.centrecsai.org which would redirect to centrecsai.org which would redirect to www.centrecsai.org and you have entered an infinite loop.
Therefore:
www.centrecsai.org ---> 301 PERMANENT REDIRECTION to centrecsai.org
centrecsai.org --> 200 OK serving the site
Perfect. This is EXACTLY what you want and what is actually your intention.
Nicholas K. Dionysopoulos
Lead Developer and Director
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