@karlo did you find any solution to this problem?
I have a similar issue, I don’t have anything in the frontend for users to update but have backend fields, and updating fields sends a password change email to that user.
I also tried keeping ACF in troubleshooting mode so the issue is with ACF. If I disable ACF and update the user’s name, no issue at all.
Can you please write here if you have found any solution?
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