Resignation

Once resign and got to know after that HR gives warning that if they dont come to office and work for 9 hours they will extend their notice period is it true does anyone faced this issue one of my colleague from other account got warning from his HR so he went 90 days entire notice period. After resignation should we go to office daily if we don’t go what will happen anyhow qvp will be zero, not bothered about qvp does they extend the notice period?