search console issues found

I installed this plugin on my site and google found the following issues:

Top 5 new issues found, ordered by number of affected pages:
The mandatory attribute ‘amp-custom’ is missing in tag ‘style amp-custom’.

The mandatory text inside tag ‘noscript > style[amp-boilerplate] – old variant’ is missing or incorrect.

The tag ‘noscript > style[amp-boilerplate] – old variant’ is deprecated – use ‘noscript > style[amp-boilerplate]’ instead.

The tag ‘link rel=canonical’ appears more than once in the document.

Custom JavaScript is not allowed.

How can we resolve these issues?

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