If you implement WPA3, that has mandatory MFP/PMF/11w.
If you know when it happens, and where it happens (near which APs and at what signal strength), you may be able to determine the location within a few meters and catch this person. Be aware that some broken client devices may behave weird and send de-auths for itself. RFProtect may assist to more effectively detect (and alert) de-auths.
------------------------------
Herman Robers
------------------------
If you have urgent issues, always contact your Aruba partner, distributor, or Aruba TAC Support. Check
https://www.arubanetworks.com/support-services/contact-support/ for how to contact Aruba TAC. Any opinions expressed here are solely my own and not necessarily that of Hewlett Packard Enterprise or Aruba Networks.
In case your problem is solved, please invest the time to post a follow-up with the information on how you solved it. Others can benefit from that.
------------------------------