webmaster crawl url errors after moving site to 'html' from 'wordpress'

1. I was using wordpress site, https://www.asianeyehospital.com. I had to move the site to html because of some serious issues.

2. Now my site is in html. The problem now is, i tried redirecting urls, for ex:-https://www.asianeyehospital.com/about-kankaria-eye-hospital/, to my new url using Redirect 301 in .htaccess file.

3. Suppose my old page is /about-kankaria-eye-hospital/, i redirect it as,
Redirect 301 /about-kankaria-eye-hospital/ https://www.asianeyehospital.com/about-kankaria-eye-hospital.php, but it is not getting redirected.
NEED YOUR HELP TEAM WORDPRESS, Thanks in advance.

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