Unable to log in. isUserSignedIn() return false

Hi everyone,
I am trying to build a distributed app on blockstack. I checked tutorials and started working on my app. I am redirecting users which are not logged in to blockstack, completing the login flow and when user comes back to my site after this flow I expect blockstack.isUserSignedIn() return true but it is false. Also it is same with UserSession. I went through examples but couldn’t find the reason.
Can you help me ?

Code? Github? Anything? Can’t really look and see what’s the issue with no code.