How to decode base64 to pdf in POSTMAN

I want to send pdf file by using Postman. Before I send it, I decode base64 in code below.

in Scripts Tab (Pre-request)

var base64 = "JVBERi0xLjMKJcT....."
var pdf = atob(base64); //Decode
pm.environment.set("pdf", pdf);

After that, I set body by using parameter environment (pdf) before in request body
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After I send request to destination I can open pdf but file pdf is empty. What should I do?

Why pdf become empty. I try converting base64 to pdf in online, PDF is not empty.