Ok, here what I got from D-Link:
WPA supports 8 to 63 ASCII characters.
Supported characters: 0-9,a-z,A-Z,~!@$%^&*()_+-={}[];:|,./<>?
They said that maybe how clients are parsing these characters maybe the issue. So your combination your using on the 890L maybe the DAP is handling or not handling your combination in your PW you set up. So try something less complex or different on the 890L so the DAP and other clients can handle the PW better. Instead of using your PW, try making something up and replace normal letters with special characters like for example:
TheQu!ckBr0wnF0xJump$OverTheL@zyD0gsB@ck
The PW doesn't have to be too complex to be secure and keep things safe.