My Apple ID and password combination work on my newer MacBook running Big Sur...but the same combination will NOT work on my older 2013 era Macbook running OS v10.10.

I'm entering the same Apple ID and password on Macs running Big Sur and Monterey, and it works. But it will NOT work on my 2013 Macbook running Yosemite (v10.10.5). I try 3 times, then I get locked out.

One thing I've noticed about this login process is that my newer Macs do flash the 6-digit confirmation code...but it doesn't matter because OS 10.10.5 never displays the enter screen for the code, so I can't enter it. It simply says that my password is incorrect.

This is a problem, because I purchased an app on the App Store using my newer MacBook running Big Sur, with the specific intention of downloading an older version of the same app to run on OS 10.10.5...but I can't even gain access to the older app download because I can't successfully log into the App Store in 10.10.5 to see and download the older version.

The app is 'Anytune' and I need v 4.1. I am following their website's exactly on how to gain access to the older version, but since I can't log in with the older MacBook, I can't even see the older app version.

What to do? Thanks in advance for any help.