Hello, I respond in bold.
did it work before from this ap? A week ago, those APs were installed. My client told me this AP it is not work fine
does it sometimes work and sometimes not? sometimes, yes, and other times, no. The corporate user sometimes they have problem to connect
is the management ip from this AP in the same subnet range as the other AP's?the same static subnet, yes
do you see any error log on the radius server from this AP management IP? I cannot access the Raius client server.