Hi!
I used the instructions by kellerman from: Nethserver-freeradius integration module - #33 by kellerman
Has been working around a year already and survived all updates.
In /etc/raddb/polycy.d/canonicalization I changed apostrophe to quotation marks
nai_regexp = “^([^@]*)(@([-[:alnum:]]+\.[-[:alnum:].]+))?$”