Are you guys still doing this thing?
You've had an invalid SSL certificate for the past 4+ months, the paypal subscription pop-up doesn't work any more, so I can't figure out how to subscribe (yeah, tried disabling all pop-up blockers and different browsers, same result), and loads of people complaining that their subscriptions aren't activating.
It kind of looks like you don't care any more. It's a shame. J-Cook used to be good when it worked.

I think J Cook is nearing the end of its life... the Developer is pulling away.
Check out this thread...
j-cook.pro/index.php/support/14-news-chi...dmap-to-4-0?start=30

So best to find another solution - otherwise you'll have problems with PHP8 and beyond.