# List Object not Callable

Hello, see the link given above. Apparently, I need 60 points to upload images. So the idea is I am trying to construct a matrix by appending lists to each row. I am not understanding the error I am receiving.

CoefficientwList is just a list of numbers. From the second picture, you can see that Separation4 maps a list to a list of lists. By typing Separation4(CoefficientwList)[i1], I am extracting the i1th list in the list of lists. I then apply the vector function to make this list a vector and then from the 3rd picture, you see I add it to a row of the matrix M. Is there anything wrong here?

If more info is needed, please tell me but I am not seeing what the issue is.