What remote are you trying to use? Sticks only work with Wi-Fi direct remotes, not IR remotes (like from an Express). If you can set up your new Wi-Fi to match your old (same SSID/network and password) your stick should connect automatically.
Also, which Roku Stick do you have? The model number is important. Most use the standard WiFi Direct remote that you can find at Walmart, Best Buy, etc. But the earlier model Sticks (discontinued many years ago) won't always work with the current WiFi direct remotes.
DBDukes http://www.dbdukes.com/Roku Ultra (4660) Roku Streambar (9102) Roku Streaming Stick+ (3810)