Recently I have changed the name of my admin, and took off the password.
at the beginning everything looked right. However, when I turned off my MacBook Pro 2017, and turned it on again,now it gives me only access to the guest mode, and my admin account doesn't available to enter at all, and the only options that I have is to enter/click the guest mode, sleep restart, and turn off the computer. I also tried to do some changes in Users & Groups. However, cause I'm in a guest mode, so I need to click (unlock to make change) and Mac just refuses to accept any username, or password.