Ah! Okay, so this is a common issue most people, have with variables.
The order at which they are declared is important, have a look at this snippet:
.....Va
.......
aV5..Va
.....5.
.......
aV6..Va
.....6.
You’ll notice that the first Va outputs nothing, since at this stage of the parsing process, there had been no assignment to the a variable yet. Orca runs from the top left, to the bottom right.