Posts and pages not publishing

Good day everyone!

I’m having problem making pages and posts. Here’s our website https://www.firstphysioclinic.com/

First the pages, when i tried to publish a page, most of the time it ended up to drafts. i also tried to rewrite it so many times but same result.I can rate it as 1 out of 5 pages published in the web. I edited it so many times but it still the same.

Same as the posts, it’s also saved as drafts. Another problem is when i’m editing old posts and publish it, the updated post is still the same as the old one. Some other post i edited was updated in the visual editor but same old post in the blog.

I’ve read the Master List post and tried the steps there.
1.Flushed caching plugins as well as the browsers caches and cookies,
2. troubleshooting with my browser (and it has issues like this ?????????? : s is undefined
??????????? : chrome://ytoolbar/content/dtxcoupon.js
?????? : 63)
3.Deactivating all plugins

The problem I found was from WP Super Cache. I cant deactivate it. It says like this:

Could not remove WP_CACHE define from /home/firstphy/domains/firstphysioclinic.com/public_html/wp-config.php. Please edit that file and remove the line containing the text ‘WP_CACHE’. Then refresh this page.

I removed it but another error pop up saying this: One or more files could not be deleted. These files and directories must be made writeable:…

I tried changing the numeric value for the nth time but the operation not permitted.

Now I don’t know what to do next. Your help will be highly appreciated. Thank you.