You're a little shy on details. What is happening? Does the TV see your network but can't connect? Does not not see your network? Does it see any nearby WiFi networks?
If you can see it but can't connect, does your WiFi password have any special characters? Roku devices only like letters (upper and lower case) and numbers.
Since you mention activate, is this a brand new set that hasn't been linked to your account yet? If so, try using an alternate Internet connection, such as a phone hotspot. That has worked for many users, and then once linked and updated it connects to their home network.
Dan
Roku Stick (3600), Ultra (4640), Ultra (4670), Premiere (3920), Insignia 720p Roku TV, Sharp 4K Roku TV, Nvidia Shield, Windows 10 Pro x64 running Serviio and Plex on a wired Gigabit network.
