Hello ! 
I actually work on a application developed with Kotlin who use the Microstrategy REST API. I need to connect with my login on the server so I use the login request ( MicroStrategy REST ). Before start development I tested REST request with REST tester on my web browser. When I do that it works I can login and I received the server answer.
But when I tried with my Kotlin application I don’t have server answer. Not even an error message.
After reading this documentation I realised there is 3 steps for login. (https://lw.microstrategy.com/msdz/MSDL/GARelease_Current/_GARelease_Archives/109/docs/projects/RESTSDK/Content/topics/REST_API/REST_API_Authentication.htm) The client send cookie information to the server. So maybe it is the problem, but i don’t understand how manage cookies.
Do you have idea how to solve this problem ? Thank you in advance !
PS : With my Kotlin application I already tried a simple request like get status to check if the client communicates with the server and yes it works.