Can't logon to local account on windows 10

There are few client laptops that he set up (so I don’t know what he did) after that it doesn’t show any local users as a login option.
When you click ‘other user’ to logon, it allows you to put in an email address and password, or a user name and PIN, it WON"T let you enter a local username and password.
I had to do some admin last night logged in as my local admin account (which it only did because LogMeIn passed the user and password to it) this morning the user didn’t have their previous logon listed at login and it made them create a new ‘Microsoft account’.
This is the second time I’ve run into this.
Why is windows 10 not letting me logon as the local user account?
It is just individual workstations and laptops, no domain controller or other servers, just windows 10 clients.
If any have any type of ideas which can help to resolve this problem then please help me.
Thanking you in advance.

Hello @Lincoln

Check username and password and try to check login with administrator or admin account.
It would be better if you share message which appears at the time of login failure.