Registration on the site stopped working after 301 redirects from index.php. How to fix?

Question

htaccess

Good day. There was such an incident. The site was accessible at index.php, made a 301 redirect to .htaccess, after which the registration and login buttons stopped working on almost all pages of the site. From the cart everything works fine. I put everything back, but the problem remains. Give it a go, good people.