Call blocked error message

Has anyone else run into this issue before? First time I’ve seen it. Is this server-related? Or some bug in Sparkle?

The site is
Thanks for your feedback!

This happens only on your phone, because you have been testing the site and tapping the phone call, only to block it because you just want to test, not actually call. iOS detects this (per-site) and after a couple times automatically blocks the call, showing that.