Because it's not like I forgot how to, I just don't. I'd hardly say it's a "problem"....

[ They could smile right now if they wanted to. But they won't!! They're too busy giving her a once-over in case there's something more obviously wrong with her that could be causing this amnesia. ]

The only thing I'm concerned over is whether or not you're joking around. [ Maybe this is an elaborate prank... ] If not, it possible something magic is affecting you, or something like that.