That sounds normal to me.
The SSID is basically a signal saying I'm here and this is my name, nothing else. It has nothing to do with the actual security settings between the router and the other devices.
You changed the encryption setting on the wireless side of the router and now you need to make the same change on the device(s) connecting to the router.
Until the security settings on both the router and other device(s) match you will not connect properly to the router's wireless side.