Have you enabled Page support in the AMP > General admin screen? If your pages use custom templates you’ll need to opt-in on a page-by-page basis as well. You can find a new AMP Enabled/Disabled toggle in the Publish metabox for a given post/page. The opt-in nature is to prevent a plugin update from causing pages from being displayed in AMP when they aren’t going to render properly. In particular, if you have custom page templates in your theme then currently you’d need to implement the same custom templates in AMP.
In any case, if you can share more details about what specifically isn’t working and how to reproduce the problem then this would help identify what needs to be done.