If you have a valid reason for missing your appointment, there is no penalty to reschedule.
If you have an appointment with United States Immigration and Citizenship Services (USCIS) but you are unable to attend, you can reschedule it. While your case will take longer to complete, there is usually no penalty for rescheduling an appointment.
Yes, COVID-19 is a good reason to reschedule your USCIS Appointment. You normally need a good reason to reschedule a USCIS appointment. “I am not prepared” or “I am not ready” is not a good reason. However, you could reschedule your USCIS appointment if you came in contact with someone that tested positive for COVID-19 in the last 2 weeks or if you are experiencing symptoms of COVID-19 yourself.
You should request to reschedule in writing to USCIS following the instructions on your interview notice. You should explain the situation and attach a copy of the interview notice with your letter. In your request, you will have to show that you cannot make the date because of circumstances that are beyond your control. Be sure to send the request to the address of the USCIS field office that will be holding your interview.
Missing your scheduled appointment could delay your case for several weeks. At the worst, missing your scheduled appointment with prior notice could result in a denial of your application. USCIS may consider your Application to be abandoned.
It is never Ok to miss USCIS interview date for no good reason. If you do not show up without notifying USCIS first, they could deny your application or close your case, forcing you to start your Application process from the beginning. In which case you will have to pay all Application/Petition fees over again. USCIS will generally only give you a new date if you can show that you had a good reason to miss your appointment—If you have a legitimate emergency or if you are sick. Keep in mind that USCIS recommends cancelling and rescheduling your appointment if you are feeling sick.
Fortunately, the inability to attend your biometrics appointment is not as critical as missing your actual interview date. If you cannot make your biometrics appointment, you might be able to do a “walk-in” appointment. To do this, go to the field office where your biometrics appointment is scheduled before your scheduled date and see if they will allow you to complete the biometrics exam on a walk-in-basis. Since this is a quick and standard process. USCIS should be able to accommodate it. Try to go at a time that the office is not likely to be very busy---Usually mid-morning or mid-afternoon on a weekday.