The goal is to have followers that will engage with your content. Having someone for followers just to increase the numbers is not long-term good, and that is what's happening to you.
What I did once and helped me a little - created a quiz on stories. Posted 30 stories at once. My views got from 500-800 to 7000!! That brought me back some followers that were not seeing my stories. After that Instagram will probably suggest my stories to them, if they don't engage, they will again stop to see my stories.
So if the content is not on points many strategies can't work efficiently. Followers need to come and engage with the content!