Channel Protection

I use this form on my website Securing Access to Streams (Authorization with Token) - Flussonic Manual, but with the time interval for the link to expire of 3 hours, they steal my channels to put on other sites and app in that interval of 3 hours until the link expires, how can I protect it to work only on my sites, I don’t want to use cloudflare .

It is an internet, there is no builtin protection that can allow you to 100% lock content on one domain because many browsers do not tell referer at all.

Consider using more complicated methods, check used agent, IP address, etc.