Hello!
This would depend on how Hostinger is doing the block. Changes to .htaccess may work in the case that your origin is returning 403 errors to Cloudflare. However if this is a network level or L3/L4 firewall block then that would mean that Cloudflare traffic isn’t even reaching your web server (and any .htaccess blocks/allows). I would recommend that you reach out to Hostinger to find out how this block is implemented and what changes can be done on their end to lift it. Ask them to help you allow the IP ranges listed here: IP Ranges