Is there the chance that your Roku device is actually connecting to your Guest Network which normally/by default is left as an open network (no password)? Did your phone and laptop require a password to be entered or did they connect without a password also?
Network configuration is either accomplished through accessing the router admin login or through an app for newer routers. This is where you would configure the Wireless Security settings. (passwords and the like.)
If you have access to your router, post back with router model number and your Roku model number. If you do not have access to your router and network to make changes, you will most likely have to contact whoever is in charge and request they make those changes for you.
As a sidenote, your Roku device is connecting and working properly though? You are more concerned with the lack of password, as I understand your question.
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
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