I went on to the IRS website for formW7. As I scrolled down trying to pick up any relevant information I came across one section that stated that if one's fourth and fifth digit in the ITIN number is 73, (there are other numbers as well that will invalidate an ITIN number) she would need a new ITIN number. Since the fourth and fifth digit of my wife's ITIN is 73, I guess she needs to renew her ITIN number. You can google IRS Form W7 and and find this.
But years ago it seems I did get a notification from the IRS informing me that she needed a new ITIN number. Just don't remember clearly. I have been using the same ITIN number for the last four or five years.
From the IRS:
"Expired ITINs: If your ITIN wasn’t included on a U.S. federal tax return at least once for tax years 2018, 2019, and 2020, your ITIN will expire on December 31, 2021. ITINs with middle digits (the fourth and fifth positions) “70,” “71,” “72,” “73,” “74,” “75,” “76,” “77,” “78,” “79,” “80,” “81,” “82,” “83,” “84,” “85,” “86,” “87,” or “88” have expired. In addition, ITINs with middle digits “90,” “91,” “92,” “94,” “95,” “96,” “97,” “98,” or “99,” IF assigned before 2013, have expired. "