Welcome to Zyxel Community!
What is the authentication method do you
use for SSID?
If all clients can’t access network at same
time, it may due to Ethernet issue or radius server didn’t response.
You can check if there is any message or
logs on device or GUI show the information of clients can’t authenticate to
help us clarify and help you on this.
From your logs the clients seem can’t pass
the 802.1X authentication.
Like you mentioned, if the traffic from device
to AP is fine then the problem may due to the communication between radius
server and AP.
Can you please check the connection between
radius server and AP?
If the problem is still there, you can enable
the Zyxel support at Help > Support request > Invite Zyxel support as
administrator, and provide the Org and Site name for us to check. Thank you.
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