BE63 - WIfi and Raspberry PI 4

For the life of me I cannot get my Raspberry PI 4 to connect via wifi to my BE63.

I've split out the 2.4GhZ network as a separate SSID, and tried setting up the IoT network.

The PI (using iwlist scan) can see the SSID and sees it as a WPA2 encrypted connection, but it just won't connect to it.

Anyone else having the same issue, or can give me some insight into where to dig to troubleshoot this?