I have resigned from my job. The employer has accepted my resignation. But after some days, my office laptop came up with an issue. The IT department told me to submit the laptop to the office so they can repair it. However, after one day, I received an email stating that due to a system issue, I have to complete the remaining days of the notice period once the lockdown is over. Can they increase my notice period in such an unethical way? And how should I handle this situation?