Did you factory reset the bridge? If you do not know how to, please let me know, I can help you with that.
Did you factory reset the router? I think somewhere (bridge, or router) some settings are remembered that no longer work for the bridge, by factory resetting them I think I lost those ‘remembered’ settings. If you can connect the router with another access point name, the combination of your router and nuki bridge, is not the problem. So it must be in some setting.