Help with disappeared column

Good morning,

I am trying to use several join operators to be able to make 1 to n relationships from several tables created previously.

That join seems to have only the new table Accessibility and the previously selected attributes. 
The weird thing is that I have not selected Id_Marcas, anywhere and it appears alone. 


Where I have the box Rename, I have renamed id to id_marcas, as I am going to do many joins afterward. I don't get the point of reusing the column as there are different joins with different attributes and tables. 

Thank you