Why is your position on the Google Search results page going down?

Let me just quote YouTube user @unrealbot3027 response under video https://www.youtube.com/watch?v=kOQnjgF7UQU

#seo

With each core update Google actually updates the knowledge graph according to the changing semantic relations between queries and the SERP changes accordingly. Your content might've been semantically top notch to Google but as soon as Google updated their knowledge graph and the semantic relations between queries changed your content is no longer semantically accurate and hence less authoritative in the eyes of crawlers. For example: During March the search engine determined the queries " solo travelling" and "travelling with a pet companion" are semantically relevant queries (maybe it found lots of people searching for solo travelling as well as travelling with dogs). So if your article on solo travelling had a subsection on travelling with dogs or pets you're displaying authority to some extent. In comes october, people might be searching for "solo travelling" and "travelling to national parks" at the same time. So the search engine determines these two to be semantically related and updates the knowledge graph. And since your site doesn't have this query answered you're demoted and a site that answered the query is promoted.