I followed all instructions to edit the canonical on rank math on my website.

Hello, I’m sorry to hear that you’re facing issues with setting the canonical URL for your post. To correct the canonical of the post “How to Become a Homeowner” on your website, you can follow these steps:

1. Edit the Post/Page: Open the post/page that contains the duplicate content by clicking on the Edit button.

2. Navigate to the Advanced Tab of Rank Math: Once you’ve opened the post/page, navigate to the Advanced tab of the Rank Math in your editor. If you’re unable to find the Advanced tab, please enable the advanced mode from WordPress Dashboard → Rank Math SEO → Dashboard.

3. Choose a Different Canonical URL: Under the Advanced tab, in the canonical URL field, simply enter the URL that you want Google to index.

If you’ve already followed these steps and are still experiencing issues, you can also add a 301 redirect from the non-canonical URL to the canonical URL. This will tell Google that the canonical URL is the main URL and any traffic going to the non-canonical URL should be redirected to the canonical version.

To do so, go to Rank Math > Redirections in your WordPress admin dashboard and create a 301 redirect by entering the URL you wish to redirect as your Source URL and the location of the new resource as the Destination URL.

If you have further questions or need additional assistance, please feel free to reach out to our support team directly from here, and we’re always here to help.

I hope this helps!

Sources:
Setting Canonical URLs in Rank Math » Rank Math
How to Fix “Duplicate, Google Chose Different Canonical than User” » Rank Math
Why Google Hasn’t Indexed Your Post, Page, and/or Website? » Rank Math
How to Fix ‘Duplicate, Submitted URL Not Selected as Canonical’ Issue in Google Search Console » Rank Math