Provided og:image url encountered an unknown error
I've encountered this same error and I checked the docs.
According to the documentation it recommends:
- Optimize images to generate great previews Image Sizes Use images that are at least 1080 pixels in width for best display on high resolution devices. At the minimum, you should use images that are 600 pixels in width to display image link ads. We recommend using 1:1 images in your ad >creatives for better performance with image link ads.
https://developers.facebook.com/docs/sharing/best-practices#images
Since adding an image which has the minimum width of 1080px width this resolved my problem.
I also had this problem recently and I fixed it by uploading a smaller file (about 1024px wide, 72dpi ~ 100kb), it worked. I had to open the Facebook debugger and ask it re-scape the page.