A user with a PSK calls you and says, “The Wi-Fi worked for a week...

In this scenario, you would begin troubleshooting by checking the WLAN-level Pre-Shared Keys.

According to the Cisco Catalyst 9800 Series Wireless Controller Software Configuration Guide1, you can configure a time-based setting for WLAN-level Pre-Shared Keys (PSKs) that will reset the key after a specified interval. This feature is useful for enhancing security and preventing unauthorized access. If a user reports that the Wi-Fi worked for a week and now it does not work, you should check the WLAN-level PSK settings and see if the key has been changed.

References: https://www.cisco.com/c/en/us/td/docs/wireless/controller/9800/17-2/config-guide/b_wl_17_2_cg/wlan-level-psk.html