removed posts from xml sitemap

total posts 6580 post
configuration of seo 1000 post per site map
so
i have 7 sitemaps
each 1 have around 1000 post
after i submitted the sitemap to google webmasterstools
sitemap 1 = 1000 post
sitemap 2 = 300 post
sitemap 3 = 800 post
sitemap 4 = 999 post
sitemap 5 = 1000 post
sitemap 6 = 500 post
sitemap 7 = 13 post

so what happend to the posts ?
why its not in the sitemap ?

it used to be right
google deindexed around 2000 post due to this issue
making me lost alot of traffic help ?

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