Weird, I have the Izzy repo and it doesn't show up.
Thanks for the link!
This is a major issue with F-Droid. I can find this via a browser, but the F-Droid app doesn't show it, even searching by name. It just doesn't exist. It happens all the time, I'm not sure why it doesn't show apps that I know are there.
I can find it on Droidify no problem and after reading your comment, I also tried on F-droid app and I can see it there as well. Maybe you don't have it configured properly.