weird, mine does too. at least they fixed the KDE calculator... mostly. before the last update it wasn't using the result of calculations to start the next calculation. so typing 2+2 then hitting enter gave 4 but if you typed +2 after that, it would error. had to type the answer if starting a new calculation. it was very frustrating.
Who knows, haven't tried it today, maybe its like the "can't print on tuesdays" bug and only triggers on certain days when I try to check what weekday a contract ends ¯_(ツ)_/¯