I Have examined the endpoints but the project is based on a microservices architecture i.e. the JWT token or authorization changes severely whenever someone logged on the server so what token I have extracted from the USER CONTROLLER(Authentication API) when I am passing that token on further requests it is showing error 401 or authorization failed. SO what should I do to configure some request sampler that every time when the test runs it fetches the current JWT TOKEN. and test runs successfully.
Looking into Introduction to JSON Web Tokens article, the tokens have
exp (expiration time)
I don't think you should be obtaining a new JWT token for each and every request, my expectation is that you need to do this only once, via i.e. Once Only Controller and refresh it only if your test duration exceeds the token life span.
You can inspect JWT token attributes using i.e. https://jwt.io/ website
I would also suggest double-checking that the token is properly extracted from the USER CONTROLLER and added to the next request, it can be done using Debug Sampler and View Results Tree listener combination.