A popularly elected representative who does not represent has failed their mandate. The "contract" of democracy is (at least morally) "vote for representation". Without the representation that person is no more entitled to be there than any other random person if you ask me.
At the very least in the next election cycle the people will know who represents them and how.
Tell that to Sinn Fein MPs who were elected to the British parliament in all the elections since 1997 but any of whom is yet to attend a single session.
Abstaining from participating in parliament when you're elected or participating in unconstructive ways (i.e. by being disruptive etc.) is a legitimate behaviour. As long as you're transparent about your intentions to behave so to your voters, removing such MPs without an election would be authoritarian.
If he/she is not transparent about this and this is/becomes a widespread problem it's preferable to decrease the duration of office terms or allow recall elections instead of instituting arbitrary rules (which will have to be approved by the ruling party/coalition and therefore will likely be designed in such a would which would favour them over opposition parties).
At the very least in the next election cycle the people will know who represents them and how.