Interface is not able to delete.!

[Nihas]

Hello, Recently I have upgraded 200D box from 5.0.7 to 5.2. I was using Two SSID' s . Users with bridged and Company_Guest with Tunnel for guest . But after upgrade I am not able to use the SSID and not even allowing me to delete the interface. How do I delete the interface?

[fordrewls]

I found that mine was attached to Quarantine VLAN. Once I toggled the Quarantine Host option, was able to delete SSID.