Strange problem of generation

[info2130]

I installed Standalone Sitemap Generator in several of my websites in wordpress or e-commerce, has always worked perfectly, but about 10 days ago, suddenly, without touching any setting, began to fail, by the thousands of pages I had in the sitemap , I suddenly only a few hundred marks.
The strange thing is that this has happened suddenly and dalo same day in 2 different sites, one in wordpress and the other in OpenCart, so I assume that the problem does not stem from the site, as the same problem occurred in 2 sites completely different and the same day.
In addition, these sites was not at all making changes, the sitemap was generated daily in a perfect manner.

This Report Generator up to 07 May:
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Sitemap created on: 7 May 2013, 17:01
Processing time: 5:01:07s
Pages indexed: 15049
Crawled pages size: 557.51Mb
View Sitemaps
-------------------------
That the Report from 08 May:
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Sitemap created on: 12 May 2013, 22:06
Processing time: 0:06:03s
Pages indexed: 77
Crawled pages size: 3.69Mb
View Sitemaps
-------------------------

What could have happened?

[info2130]

Add that the two sites are on 2 different servers, then exclude also the problem of the server.

[info2130]

No one knows how to help? 

[XML-Sitemaps Support]

Hello,

could you please PM me your generator URL and an example URL that is not included in sitemap and how it can be reached starting from homepage?
 

[info2130]

my problem is identical to that described in this post:
https://www.xml-sitemaps.com/forum/index.php/topic,8283.html

But I have not done any changes to the site or server, suddenly overnight, began to capture about 10% of the pages that caught the previous days.
This has happened in my 2 sites that reside on different servers, so it can be a server problem, these 2 sites are also built with 2 cms platforms completely different.

[XML-Sitemaps Support]

Ok, please provide requested details in PM so that we can check.