How Should I Approach Agencies for Remote Work? Feeling Stuck as a Freelancer!

I am a WordPress designer and developer, and I am struggling to break into the remote job market. How can I approach agencies to land a remote job?
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Back in 2014, I started my freelance journey. I was mainly offering WordPress website setup and customization services, working on platforms like Fiverr and Upwork. Things were going well until 2016 when I discovered affiliate marketing, and it was a game changer. I built websites, wrote content, did SEO, and made enough money to buy my first house. Life was good, from 2016 to 2019, I was riding high.

But then... 2020 hit, and everything crumbled.  
Google's frequent updates killed my affiliate websites, and my income dried up. I had invested heavily in those sites and ended up with nothing. By 2021, my affiliate earnings were gone, and I was back to freelancing to make ends meet. Now, my freelance income hovers around $1,000 a month, which just is not enough.

Currently, I offer WordPress services: website customization, landing page design, Elementor, and Divi builder expertise. I have also worked with Wix and Shopify. Beyond web design, I have extensive experience with email marketing automation (Mailchimp, Aweber, GetResponse, ConvertKit, and more). I have even built lead capture landing pages and worked with platforms like HubSpot, ClickFunnels, and LeadPages.  

Yet, despite all these skills, I am feeling stuck. Why? I see people with less experience getting $1,500+ remote jobs, and I can not seem to break through. I am frustrated because freelancing means endless job applications, constant communication, and dealing with clients around the clock—sometimes for very little money. And then there is the challenge of bad clients who take advantage of you, ask for endless revisions at the same rate, or give poor ratings that can ruin your profile.
Today, a Fiverr client Cancelled the project even though I successfully completed it. He changes his mind and comes up with a new design each time.

I have decided I want more stability. A remote job, even project-based, would provide that. I am not getting a suitable job, so now I am learning video editing! It looks like I am doing endless....

So, here is where I need your advice:
How do I approach agency bosses to secure a remote position? Where should I focus on building a more stable income stream? Any tips or strategies would be appreciated.

My frustration reaches a level where I don't know what I should do next!