Good afternoon, Alex. You are correct, SQF requires you to have verification activities, and a verification schedule.
2.5.2.2 A verification schedule outlining the verification activities, their frequency of completion, and the person responsible for each activity shall be prepared and implemented
Do you have a procedure that states you do a monthly verification report? If so, then you are out of compliance with your own set verification schedule. In that case, I would absolutely give myself a NC and open a CAPA. As part of that, I would do a late verification and file it with the CAPA as the correction. I'd then drill down and get to the root cause of WHY it was missed, and address that in my preventative action(s).