@ahmedkaludi seems that this kind of issue is still unsolved – I have a similar validation problem
on the following page (and several others) I have a similar issue
https://www.cucina.li/prodotto/corso-di-cucina-creativa-invernale-online/amp/
The following tag generates 2 errors in Google Search Console
<amp-img src="https://www.cucina.li/wp-content/uploads/2022/02/Corso-di-cucina-creativa-invernale.jpg" alt="Corso di cucina creativa stagionale - inverno" width="1080" class="show fadeIn i-amphtml-layout-responsive i-amphtml-layout-size-defined i-amphtml-element i-amphtml-built i-amphtml-layout" fadein="" :="" height="1080" layout="responsive" i-amphtml-layout="responsive" data-hero="" i-amphtml-ssr="" i-amphtml-binding="" i-amphtml-auto-lightbox-visited=""><i-amphtml-sizer style="display:block;padding-top:100%" slot="i-amphtml-svc"></i-amphtml-sizer><img class="i-amphtml-fill-content i-amphtml-replaced-content" decoding="async" loading="lazy" alt="Corso di cucina creativa stagionale - inverno" src="https://www.cucina.li/wp-content/uploads/2022/02/Corso-di-cucina-creativa-invernale.jpg" i-amphtml-auto-lightbox-visited="" data-hero=""></amp-img>
The 2 elements “fadein” and “:” shall not appear in the <amp-img> tag
The problem started appearing after mid January 2022
