Lingua Franca task 14 destroys my command line

Hi, super stuck on task 14. So I know I got it wrong, and typed in the code:
wc -l | grep 0

I’ve seen the correct code on forums, but the above removes my input title, or directory title or whatever its called, and now I can’t input any new commands at all aside from completely shutting down Terminal.

Just wondering if there was a solution to this because I’m sure I’ll be making that mistake a lot and I don’t want to have to go through a hard reset every time.
Cheers