I’ve always replied to my blog comments from the Edit Comments page in my Dashboard. Suddenly, today, I can no longer do that. If I click on Reply, instead of the usual reply box popping up, the screen scrolls to the bottom of the page. I haven’t changed any WP settings.
I’ve done all that more than once. I’ve even rebooted my computer. There’s no problem leaving comments. I tried to reply to the comment you left. The reply function works from the Dashboard, but not from the Edit Comments page.
Better yet, just wait it out if you can for a couple hours and see if it clears up. There are quite a number of bits of weirdness right now. If staff is rolling out code, it could be a little flakey for a while.