Overdubbing problem

Hi everyone,
I am using Audacity 3.2.1 on Windows 10, and as soon as I open a music track and then try bto mix speech with it (overdub) the following happens:

I open a new mono track (where the speech is supposed to appear) and I select it, but when I click “RECORD”, Audacity begins to record at the end of the music track (the first track).

Overdub is checked in th Transport menu, the input and outpuy devices are set correctly, so I have no idea what is causing this.

Any ideas/suggestions, anyone?

Thank you in advance.

Audacity preferences: recording, “record on a new track” …
https ://manual.audacityteam.org/man/recording_preferences.html

That did the trick.
Thank you for your help.