1. First and foremost, you must check the page source of the URL in question. Search for the og:image tag like in this Video: https://i.rankmath.com/aJCccE
If the og:image tag is not found, that means Rank Math is either disabled or not able to print your social tags. Once done checking if Rank Math is enabled, you must check why it isn’t able to print social content by following this troubleshooting guide: https://rankmath.com/kb/check-plugin-conflicts/
Make sure to follow all the instructions carefully.
2. Assuming the og:image tag was found in step 1, we can proceed to find the issue.
Scenario 1: You are using minification on your website and your cache plugin is inputting too much inline CSS into your page source that your OpenGraph tags are pushed way too down your page’s source:
If this is the cache, you must move your inline CSS to a file because Facebook and other social networks will only look for OpenGraph tags in the first 60kbs of your page’s source. If they don’t find it, they will assume you haven’t added them. They don’t want to waste their resources crawling huge pages looking for OpenGraph tags.
Scenario 2: The gain browser cache option in most cache plugins like W3 Total Cache is known to not play well with Facebook’s OpenGraph detection. If you have it enabled, disable it. The option for W3 Total Cache is at WP > Performance > Browser Cache > HTTP (gzip) compression
Then, clear your website and server cache (including Cloudflare – if enabled)