User Activity

I tried to register an end-node on TTN, but it does not recognize the DevEUI.I watched this video:https://www.youtube.com/watch?v=8KNfrWoa1fw&list=PLnMKNibPkDnHZyJtMRpWSs41CWhPouRwq&index=3error:I have entered the DevEUI here: (I copied the id that i...