Transpose::nmtx
An error occurs because the argument in Transpose is a vector rather than a matrix:
Transpose[{1, 2, 3}]This shows a valid matrix argument in Transpose:
Transpose[{{1, 2, 3}}]You can use the permutation specification {1} if it is necessary to apply Transpose to a vector:
Transpose[{1, 2, 3}, {1}]