How to get rid of the spree discount pop up on my iPhone 8

This is the method that just worked for me. I hope it's permanent. This method doesn't require you to clear all your cookes or website data.

First, close the window that has been hijacked and quit the Safari app. Then, go to Settings>Safari>Advanced>Website Data. Type "spree" in the search box and you should see something like "spreediscount.com." Delete that by swiping to the left or select edit and then select the red box with the minus sign. Then, restart your iOS device (I was having this problem on an iPad). After your device restarts don't open Safari to see if the problem has been cured just yet. Before you do that, repeat the above steps and see if anything comes up when you do the "spree" search. If it comes up again, delete it again and restart your device again. I had to do this three times before it stopped showing up. Each time the data amount got smaller. Finally, the search revealed nothing related to spreediscount. Success! I'm now on they same eBay webpage that was being hijacked and it all looks good.

Good luck, everyone. I hope this helps.