The cooling system air flaps are particularly low on Ionic 5. Several reports show the vulnerability in cold/snow conditions, affecting climate control seems to be the key issue: Source: https://www.reddit.com/r/Ioniq5/comments/scg2jm/ioniq_5_air_flaps_not_closing_after_cold_week_in/ Makes sense, I know from experience when snow/cold conditions occur, the radar in my Kona Ev (located at approximately the same position) gets bunged up with snow and slush which causes an error to the forward collision detection system.
Did you wash the car recently? With the temperatures we have had recently, it is a really bad idea to wash any car, unless you have a heated garage you can let it dry in. I bet that's the problem. Water got into the hinges and it froze over.