Perhaps a better subject would have been "What does error message 11r Key Lookup Failure mean".
802.11r is a standard protocol for helping wireless clients roam to a better access point. The keys used are those for the 802.1X authentication and need to match. I'm not sure why this happens, but should only mean that the roaming event is a little bit slower than is would be if the keys matched. If you get loads of those messages, contact Mist support.
Sent: 11-14-2022 14:01
From: Anonymous User
Subject: What does this error message mean
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What does this error message mean for a wireless client - 11r Key Lookup Failure