I am not able to Switch user login in Macbook pro

to be used effectively by more than one user, you MUST disable Automatic Login [of one user, ONLY]

System Preferences > User&Groups > [authenticate as Admin] > Login Options

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Hi,

Just wonder if you've read the following article already.

Switch quickly between users on Mac – Apple Support (AU)

Switch quickly between users on Mac – Apple Support (AU) does not seem to have to do with the above problem of the login screen.

The same happens to me, after a stand-by: you can you choose any user, but it switches anyway to the admin login, no way.

It worked once...

The "Approved Method" for logging in to an Apple computer is to use your username and password.

if your username and password are not working, you can occasionally, under just the right conditions and with an Internet connection, force it to login with your Apple-ID. Apple-ID is a desperation measure, NOT a mainstream method of logging in.

if you were to complain to apple support, they would be really nice about it, but coax you to use your username and password.

I have 2 users and 1 admin.

If one of the 2 users chooses its own icon at the login screen after a stand by, their icon appears less the 1 second, then the icon switches form the one of the user to the one of the admin icon automatically. No way to insert psw for users (or it does not work on admin icon)