You can try search info about google panda seo https://www.to-the-top.ca/google-panda-fast-seo/ I got same for my healthcare websites. I prefer to use white seo strategy. A white-hat SEO strategy uses recommended best practices and user-focused tactics to optimize your site. For example, a white-hat SEO strategy might include producing helpful content, improving page speed, and inserting keywords naturally
SEO is always beneficial for a website to increase traffic and achieve better ranking. Reaching the target audience is a difficult task and SEO helps you to meet your expectations worldwide.