@BodhiEshin 

When you upgrade the firmware, is there something wrong of the EAP? (When we upgrade the firmware, if the power is off, the EAP device will brick.)

Check if the Omada Controller is managing the EAP successfully. If the EAP is disconnected from the Omada Controller, some features of the EAP may work abnormally. 

Please check if the EAP device can work normally, for example, create another SSID without portal, then try to connect this SSID to check if you can access the Internet. 

You can also reboot the Controller and EAP to have a try.

@forrest We have made sure it has upgraded correctly. We have also reset the unit, uninstalled controller and have tested again with the same results.