I got warning from google webmaster that I have issue with some of AMP pages on one of my site ...
It was something with use this mark: grammarly-btn ...so what happened .. I was creating new post in Chrome but Grammarly for Chrome was enabled and it seem that in text that I was writing Grammarly insert some code inside.
After disabling Grammarly extention , deleting block, inserting new text block and copying text as plain text, warning from google webmaster after checking in their AMP tool gone.
So DONT use Grammarly for Chrome when writing blog