Strange Google SERPS issue

SEOHermit said:

I have several posts that have been appearing for several keywords on page 1. Then a few days to weeks later they begin showing up in the serps with the same meta descriptions as some of my other posts and they are then dropping off from page 1. Also, I am seeing that I have duplicate indexed versions of the post indexed under archive and category pages as well as the individual post. It is now happening on other sites I have built as well. It is very disheartening and has happened on sites I have had out there for four years with none of these problems in the past. Hope someone can point me in the right direction to find the root cause

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SEOHermit said:

I have several posts that have been appearing for several keywords on page 1. Then a few days to weeks later they begin showing up in the serps with the same meta descriptions as some of my other posts and they are then dropping off from page 1. Also, I am seeing that I have duplicate indexed versions of the post indexed under archive and category pages as well as the individual post. It is now happening on other sites I have built as well. It is very disheartening and has happened on sites I have had out there for four years with none of these problems in the past. Hope someone can point me in the right direction to find the root cause

Click to expand...