WordPress Post editor redirects to page not found

Hi, I have a self-hosted WordPress blog. The URL of the blog is https://digitalsanthosh.net

I’m not able to edit and update one of my blog posts. Because it shows me a page not found 404 error.

This is the link that is showing error https://digitalsanthosh.net/wp-admin/post.php?post=5213&action=edit

But the post is loading correctly for users from the front end
https://digitalsanthosh.net/how-to-start-a-blog/

I’m able to edit other posts and update them.

But this specific post I’m not able to update. It is a bit lengthy post as well.

I tried all the troubleshooting methods. I disabled plugins and did everything. I even contacted the hosting provider.

But until now I did not get any resolution.

Could you please help me with this?

Thanks

The page I need help with: [log in to see the link]