Transferring data from one block to another

Good day!

I can’t transfer the data received in one block (POST request). Which are needed as the basis for the block following it (POST request). I am writing about the variable {prospectiveSaleId} . As you can see in the screenshots…
I need the resulting POST request response: https://api-…/prospectivesales/create/v4 ,
part of the response, the {ProspectiveSaleId} variable. Use as a basis for the following query:
https://api-…/prospectivesales/{ProspectiveSaleId}/postpone . However, the error sent by the server is: "message:“The value ‘{ProspectiveSaleId}’ is not valid.”
Doesn’t let it dry out.
Question: How is it possible to transfer / use the received variable and its value as the next POST request? As you can see in the screenshots in attach file…
It is necessary to supplement that on the pages of the site, and on this forum. I did not find an answer to my question. Please help me.