I've had a Little Giant water heater since Nov 2021 and it's still working today. You could take it apart and see if some wiring has come loose. Or using a multimeter or circuit tester: touch one probe to an element terminal & the other to the metal tank, it there's a reading there's a short &...
It gets nasty in there when I do the deep clean, so I always wear a mask when I do. I understand some folks get all antsy-in-the-pantsy trying to breathe in them but luckily masks don't bother me.