Cannot compute_cost course 2 week 3

Exactly. Where does it say that transpose and reshape are the same thing? Transpose is a very specific mathematical operation, not simply a reshaping of an array. Reshape has several different methods as well, none of which are necessarily equivalent to transpose in general (although you may get lucky in some “degenerate” cases with only one non-trivial dimension). Here’s a thread which discusses reshape in the context of the “flatten” logic in Week 2 of Course 1, but if you read the whole thread it gives some examples of how reshape traverses the input array in order = ‘F’ or order = ‘C’ mode.