I now got an email saying:
During this step, USCIS initiates the background checks of the applicant/petitioner and identifies issues that may need to be addressed either during an interview or by asking the applicant/petitioner to submit additional information or documentation. USCIS reviews the applicant's/petitioner's criminal history, determines if there are national security concerns that need to be addressed, and reviews the application/petition for fraud indicators. If you have filed an I-485, I-589, I-751, N-400, I-90, I-821, I-131 or I-765, you can expect to receive an appointment notice to appear at an Application Support Center to have your fingerprints and/or photographs taken. The timing of your appointment is determined by the number of applicants ahead of you that also need a biometric appointment. We try to schedule biometric appointments as quickly as possible and in most cases you will receive your appointment notice within 30 days of submitting your application. We will send your appointment notice approximately 14 days ahead of your scheduled appointment. It is important that you keep this appointment. If absolutely necessary, you can request that your appointment be rescheduled however, please be aware that rescheduling may delay the processing of your application. Please follow the instructions on your appointment notice if you need to reschedule. Occasionally, you may receive an appointment notice to appear at an Application Support Center to have your fingerprints taken when you have filed a form other than those listed above. In these situations, you may receive your appointment notice more than 30 days after submitting your application or petition.
I took my biometrics in September. I had my interview on May 3rd. I don't understand what's happening. Is there anyone else who has encountered a similar situation?