social login with temporary user

hello every body I wish I will find answer for my question here .
I am working on mikrotik hotspot system with social login , I don’t want to add facebook, google in walled garden , I want to create temporary user who has 3 minute full internet access , now when user redirect to login page he will connect to that user automatically , and user has to make social login before the 3 minutes of user will finish .
so if user connected to temporary user automatically and he press on login by google button , I have to disconnect him from temporary user and connect him with his email . but to make new login I need new chap code for new login , how can I get that chap code .and how can I disconnect temporary user and reconnect the user with his new account .
I wish I explained my problem clearly