AMP page: https://www.acuvuearabia.com/freetrial-amp canonical page: https://www.acuvuearabia.com/freetrial
The AMP page validation is correct on validation page: https://search.google.com/test/amp?id=91w2VdfmpqD6XRdsMZYR7w enter image description here but in Google search result it show "Missing amp" icon:enter image description here Any suggestion with AMP page's setting?
As you said, the AMP page is validated and it has been already cached by the AMP Cache. Read here about the AMP Cache url format.
It can be that the AMP and the canonical are different in content so they are differently indexed. I don't think this is an AMP issue, but a SEO one. You have to create the correct search query for the AMP to appear in the search results and then you will find your AMP in the results. It is important that the content of your AMP and the canonical is the same!
