How to restore admin access to windows server 2012?

Question

Windows

Good day everyone, tell me about the problem:
There was an urgent need to create a domain in a small network, for this I installed Windows Server 2012 even earlier, finally I was going to raise the domain, I used to raise the domain without problems for 2008, and then a nuisance arose - added the Active Directory role Domain Services, started creating AD, like this guide https://jakondo.ru/razvorachivaem-kontroller-domen..., created a forest, set a password that was requested during the setup process, a password for restoring directory services mode (DSRM), then a bunch of system messages about installation and configuration went on, after which Windows rebooted itself, after which the problem actually arose, I can’t enter it , when raising AD, Windows did not ask me to create an AD administrator account, when I logged into Windows, but already in the created domain there is the name of the same account in which I worked before creating the domain, i.e. locally, Admin, but the old password is not suitable, the DSRM password is also not suitable, I tried to log in as before locally, i.e. substituting the name of the computer as a domain, i.e. computer name \ Admin and the previous password, but this also does not work, tell me, how can I still go into Windows? How to use the DSRM password, or how to return everything as it was by canceling the creation of the domain,