I use Webmaster Tools for my website and I have removed duplicate titles in my site. But it is not getting reflected in Webmaster Tools.
Is there any reload to view the changes in HTML Improvements?
No there is not, Google will reflect the changes when it crawls and processes your pages again.
This whole process may take from days to weeks and you can't force Google to do it right away. Even if those conflicts are already solved, they could still be showing up in Webmaster Tools.
It may also help to trigger re-crawling within a day according to this Google Webmaster Central Blog:
The Fetch as Googlebot feature in Webmaster Tools now provides a way to submit new and updated URLs to Google for indexing. After you fetch a URL as Googlebot, if the fetch is successful, you’ll now see the option to submit that URL to our index. When you submit a URL in this way Googlebot will crawl the URL, usually within a day. [... ] if you’ve got a URL whose crawling or indexing you want to speed up, consider submitting it using the Crawl URL form or the updated Fetch as Googlebot feature in Webmaster Tools.
Speeding up crawling may help to get Google Webmaster Tools to reflect changes quicker.