REST API call works in Postman, but getting 403 in VuGen

Question

I have a REST API call that requires a JWT token. The call works fine in Postman, but I am getting a 403 in VuGen when trying to run the script. The call is the same and I have added the header with the authorization token. However, still getting 403. Anybody has any idea what should I try out (I am new to VuGen)?

web_set_sockets_option("SSL_VERSION", "TLS1.2");

web_add_header("Authorization", "Bearer xxxxx");    
web_add_header("Content-Type", "application/json"); 

web_custom_request("test - v1",
                   "URL=https://{env}/flights/v1/offers",
                   "Method=GET",
                   "Resource=0",
                   "EncType=application/json",
                   "Mode=HTTP",
                   "Body={}",
                   LAST
                  );