Twitter is one of the biggest social platform in the world. We need to publish post on twitter wall. It is a really easy stuff. But it may happen sometime that image is not showing when trying to publish a twitter card.
When you will get a problem like everything is working but image is not showing, you will need to check the link over https://cards-dev.twitter.com/validator .
If it conform that your site is whitelist, and your meta tag is for twitter image is twitter:image but not twitter:image:src ….
Then if it still not works you will need to update you robots.txt which you will find on your site root directory with this code…
So it may look like …
Then check the URL again on https://cards-dev.twitter.com/validator . You will see the image is updated…