RADIUS Disconnect throws error or warning

Running 6.38.5 on hAP Lite. Have hotspot setup using RADIUS authentication. Works great.
Using freeRADIUS 2.2.6.
I have COA configured. It sends packet to hAP. if I send User-Name, NAS-IP-Address, Framed-IP-Address the hAP replies with Disconnect-NAK, Error-Cause = 406. It does the disconnect, even though it NAKed the request.
If I send ony the User-Name, the hAP responds with Disconnect-ACK, but logs in hotspot, error, info,debug Radius disconnect with no ip provided. It also does the disconnect.
What needs to be sent in the Disconnect message so that the hAP replies to RADIUS with Disconnect-ACK and does not put a hotspot error in the log?