Extreme rank drop

I started consistently publishing blogs about two months ago, then made significant site changes to correspond with shifts I have made in my business about 3 weeks ago. Over the past two months I started ranking higher each week for a keyword I am targeting, but this past week I dropped suddenly from 9 to 62 for this keyword in SERPS. This keyword is one of my main targets.

There are no manual or security actions. Everything is indexed. Competitors haven’t made significant changes, and now a bunch of sites with thin content are significantly outranking me.

I am relatively new to SEO. I have looked into everything I possibly can before asking for help here. I’m trying not to panic. Ive spent the past six months developing highly valuable content for my niche, so this is disheartening.

Can anyone tell me if this extreme loss in ranking is normal and what might have affected it?

I appreciate any knowledge and insights you might have.