I found this solution that David had posted and it did work. - https://community.shopify.com/c/shopify-discussions/hacker-cloned-my-store/td-p/463581/page/2 I had to remove www in the first line it did work. passing it on to you and others. excellent...

actually instead of wwwdomaincom I did domaincom instead it seems to work. i'll do some more testing. Overall, excellent suggestion. thank you 

David, Thank you for your post. You're super helpful. I put this on my Theme, and it did work, as it blocked the duplicate site from loading. but it also caused my site to go in a loop and didn't load until I removed the script.