always do a monthly site audit, use screaming frog to check your website if there is a broken links on, missing h1 and meta tags.
Create valuable content once or twice a week to recover, google would love that as he sees some updates on your website.
Create a backlinks with high DA/PA. Create more valuable content it will take long but it will effect on the long run.
create also a blog which gives a positive feed back to your company with a longer and optimized content than the bad blog content.