How to add a link to a non-AMP version of a page in Wordpress?

Question

Accelerated Mobile Pages

Good day to all!
I ask for hints. The problem is this - I made pages using the standard AMP plugin. They have a link to the non-amp version of the article. This link doesn't work and throws an error. I dug into the code - there is some tricky non_amp_link () function. Most likely, the problem is that I have arbitrary links recorded as mysite.ru/index.php/ru/category or material. The link generated by the non_amp_link() function loses index.php somewhere on the tail, and the rest is all written correctly.
How would I fix this without changing the permalink structure? :) Tried through permalink - doesn't work) Another link to the current amp page is added.
Thank you for your attention.