I485 interview ( interview canceled- no file)

[Samsun123]

After 9 months wait Received a appointment letter in Feb, 2020 for appointment today Mar 17, 2020. Went to the appointment, the person at the counter call me to the counter and said my interview can’t happen today because they haven’t received my file yet and my interview will have to be rescheduled.

Is this normal ? How can they not receive my file if interview letter was sent a month before.

How long will it be until the appointment is rescheduled.

Did someone have the same experience? What can I do about it please help.