Is console app parameter in react.js code outside serverless.yaml?

Serverless Framework
#1

I want to print an env variable to console.

I added following veriables in parameters of Serverless app console

in dev: "TESTNAME" : "dev test name"
in prod: "TESTNAME" : "prod test name"

And in js file in my React.js project, I tried

console.log(process.env.TESTNAME);

But it returns nothing.

How come it doesn’t work?

#2

Adding additional .env files like
.env.dev
.env.prod
solved.