Another Align tool question

Back with another Align tool, Translate tool Question. I am making a simple box out of panels I created using the pattern tool. I don’t know if this is a bug or I just don’t understand things. I have tried both ways. Using the align tool to align each panel to the box. The top is open on my box. I think, or I thought that when I used the Translate tool before and aligned each panel the app made a box automaticly connecting each pane. So, when I double tap on the box every panel is connected together. Therefore, I can then go to each inside corner and drag to create a chamfer. To strengthen my Box. This was GREAT, Love IT! But now I can not figure out how I did it. I have aligned each panel but the box is still make up of individual pieces. I have tried using “Union” but that really does not work. As I have said in several other posts. The Union tool seem on the surface to be what I want but it is just to slow,etc. when I try to Chamfer an edge, etc. Is there another technique to preform this function.

Thank You

Can you please upload a short video of this case?