API block not mapping response to variable

I am using a API block, in order to send a POST request and to map a json response value to a variable.

When I do a “Test Request” on the block, everything works fine and the response value is stored/mapped to the variable.

But when I go to “Prototype” and start a test, the variable is always 0 (zero). I couldn’t find any resource on this.

It is almost like the request jumping to the next block (voice) without waiting for the response.

Any hint?