Can you use an ethernet cable to get connected? It is probably just a router setting getting in the way. What is the model number of the Ultra and what brand modem/router model number are you using?
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
Insignia RokuTV, Ultra 4660, Premiere+ 3921, Express 4k+ 3941, Streambar 9102