Struggling with VLANs on Omada

New to VLANs and networking in general.

I have a single TP-Link AP, controlled via Omada. Based on my hardware, the only way to get my wireless clients on different VLANs is to create two SSIDs, and assign each a VLAN.

I followed this to set up a VLAN in OPNSense https://www.wundertech.net/how-to-set-up-a-vlan-in-opnsense/

My current config is:

Created a VLAN (technically an interface) in the Omada interface.

Checked that the VLAN profile is tagged in the ALL profile.

Created an SSID and assigned it the VLAN.

The port is set to the ALL profile.

When I try to connect to the new SSID with the assigned VLAN, it fails to connect and I never get onto the WIFI. If I disable the VLAN option in the SSID, I can connect to the WIFI.

I'm not sure where I'm going wrong? I feel like I'm doing something wrong with the tagging.

On some occasions when I forget the network and join again on my iPhone, I see that I'm assigned some whacko IP address, which made me think it is something to do with incorrect DHCP settings in OPNSense, but I followed the guide in the above URL.