Any good SEO consultancy services?

After the repeated core updates this year, SEO has been taking for all of my sites. Whatever we do doesn't seem to generate results. We're a SAAS company and trying to look for a SEO consultancy. My first thought was Neil Patel. Do you guys have any experience with this guy? Or can anyone suggest me a good SEO consultancy that can work with enterprises? Thanks! Edit 1: I have posted on behalf of my firm. Please understand that I'm not at liberty to share any details. Also, I am looking for proper agency recommendations not any freelancers. Thanks.