how to change account supervive on steam?

[Король Доты]

I accidentally clicked yes during installation, yes yes, and in the end I have a new account, although I was still playing in beta and I want to play from it, in the browser I logged into my account, but in Steam, even when reinstalling, it automatically logs in to another one

[Bartsim23]

Ever figure this out?
I had the same experience and would like to use my old account. But made one without thinking.