Google Error: Amp URL is not an AMP

I have a Google Search Console error on 4 pages: URL is not an AMP. The pages are:
https://www.intimacywithgod.com/videos/amp/
https://www.intimacywithgod.com/free/amp/
https://www.intimacywithgod.com/2019/01/26/jesus-your-first-love-2-idols/amp/
https://www.intimacywithgod.com/2019/01/05/can-know-god/amp/

On the top of my page https://www.intimacywithgod.com/videos/amp/ is the following error message: Warning: strpos(): Empty needle in /home/intimac2/public_html/wp-content/plugins/accelerated-mobile-pages/includes/features/functions.php on line 494

This just started several days ago.

The page I need help with: [log in to see the link]