Need help re re-connecting EAX18 Extender

We have had the Netgear EAX18 Extender for awhile. It was connected and working fine, as far as I could tell. We then changed the password for the network the extender was extending (long story). Since changing the network password, devices (desktop, tablet) in the area that the extender served have been dropping the connection repeatedly and frequently not accepting the network password (saying it is invalid).  

I was thinking that perhaps, since the network password was changed, that the extender would need to re-establish the connection to the network. However when I try and do that, using Nighthawk, for example, I don't see the Netgear_Ext network show up. The only networks that show up are those we are trying to extend. Do I need to do a factory reset to be able to re-establish the connection?