How to determine for what reason Yandex discards the page?

Question

Search Engine Optimization

The second time, after reaching the first page, at the right request, Yandex immediately throws our site far back, on page 15-22 of the search results. Please tell me how can I find out why this is happening and how to solve this problem?

Answer 1

1- see which particular page appears in the top ten and which page is shown when the positions drop. It is quite possible that these are two different pages relevant to the same query.
2- check the optimization of commercial factors, https://habr.com/post/415991/
3- does the site design meet modern requirements?
4- How long has this situation been happening? If for a long time, then one of the top three points is likely to solve it. If recently, then you can wait, see a hundred will be further, perhaps it will be fixed in the top.

Answer 2

Look at the webmaster plus updates don't go straight in a row, so I think you're just not looking at the positions correctly