Check out this tutorial. If you like it I suggest bookmarking it. Will work with 5.7 btw.
I use it pretty much verbatim for all my API projects.
https://medium.com/modulr/create-api-authentication-with-passport-of-laravel-5-6-1dc2d400a7f
Not really sure what CreateFreshApiToken has to do with it (it doesn't).
Also be sure postman is set up correctly. I set up presets like:
My login example:
Route : /api/auth/login
Tests tab (this will set the enviroment variables. NOTE on token, my tokens come back with Bearer already concatinated on, different then tutorial above):
var data = JSON.parse( responseBody );
pm.environment.set("token", data.data.token);
pm.environment.set("expires", data.data.expires);
// any other variables you need set
Create an environment (upper right) with expires and token. Initial values empty.
Make sure you new enviroment is selected
Now back to Headers tab, on the right click Presets and manage presets:
I create two, first one I call basic then click "bulk-edit":
Accept:application/json
Content-Type:application/json
the second one I call basic w/auth and once again click "bulk-edit":
Content-Type:application/json
Accept:application/json
Authorization:{{token}}
The token in {{ }} is the enviroment variable and is set automaticly when you "login"
Hope that helps!