Message appears after the conditions have been accepted

Hi, I’ve installed this plugin in many sites and it always worked fine.

But in a site that I’m working right now, it doesn’t work as it should.

When I accept the message, it doesn’t set the cookie “cookillian_opt_in”, so when I continue the navigation in this site the message appears again.

I’ve tried to work with another theme, change the WordPress version, disabled all the others plugins… and still not work.

Any idea of where is the problem?

Thanks in advance.

https://www.ads-software.com/plugins/cookillian/