Authentication error after deployment: 'jwt must be provided' – discrepancy between local server and production deployment

Question

When I deployed my project, when I hit login, it throws an error:

jwt must be provided

But on my local server, it works perfectly fine.

Note: I have used Random JWT_secret key = wyufgeeubw

My middleware/auth.js code =>

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My routes auth.js code =>

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I have entered the jwt secret key in environment variable in the render and tried re deploy both frontend and backend code