I can download Monterey 12 or any other

According to MacTracker, Apple used Model Number A1398 for several Macs:

• MacBook Pro (Retina, 15-inch, Mid 2012) – which can run Catalina, but nothing later
• MacBook Pro (Retina, 15-inch, Early 2013) – which can run Catalina, but nothing later
• MacBook Pro (Retina, 15-inch, Late 2013) – which can run Big Sur, but nothing later
• MacBook Pro (Retina, 15-inch, Mid 2014) – which can run Big Sur, but nothing later
• MacBook Pro (Retina, 15-inch, Mid 2015) – which can run Monterey, but nothing later

To determine which of these five models he or she has, the OP can use the About This Mac dialog in the Apple () menu.

Old versions of the Mac operating system are available here:

How to download and install macOS - Apple Support

To downgrade the OS, it will be necessary to do a "clean install". Back up applications and data first, erase a disk (doesn't have to be the current one; could be a spare if one wants to install the old version of the OS on a spare), install on the empty drive, then restore applications and data.

Note that if the OS upgrade "upgraded" the format of the iTunes and/or Photos Libraries, going back could be a bit "interesting". (The old software might not understand any format changes its newer counterparts made.)

Note that if one upgrades to Catalina or later,

• 32-bit applications will stop working
• iTunes will go away, replaced by separate applications: What happened to iTunes? - Apple Support

According to your mention, MacBook Pro A1398 is a MacBook Pro Retina 15 - Mid 2015. This is a device fully compatible with Monterey.

Mamaikin76 wrote:

Hi,

Why can't I install the software higher than 11 Big Sur? I uploaded Big Sur and now I can’t use Word or Excel and I have a constantly dark background of the Browser pages that cannot be changed. How can I update the software to the Monterey or Ventura? Or do I need to return to 10.13. Siera? What to do (MacBook Pro A1398, 2015) because I can not work?

And may be somebody knows what kind of mail I may write to apple support about this?

Thank you!

Regards

https://discussions.apple.com/content/attachment/0c816fc3-4214-418e-ba6f-7eb632e87fa7

macOS Monterey is compatible with these computers

A 15-inch mid-2014 MBP would have originally come with Mavericks (10.9.4). It can run

• Mavericks
• Yosetime
• El Capitan
• Sierra
• High Sierra
• Mojave
• Catalina
• Big Sur

That's 8 major versions of the operating system (the version that came with the machine + 7 upgrades), and Apple didn't charge extra for any of the upgrades.

I remember back in the day when a retail Snow Leopard upgrade cost $129, and that was low-priced compared to a retail Windows upgrade that might set you back $200.