FindMy doesn't match my User ID for iCloud.

alias4you wrote:

2020 MBP Has an issue that I may need Apple for. My MBP has no activation lock and I am the only user. I am signed into iCloud. Currently if I attempt to turn on FindMy, it asks me for a password to the previous owner. FindMy is turned OFF. Nobody except me is signed in the MBP. I booted in recovery and erased the HD via Disk Utility, then recovered Sequoia OTA. After a complete format it STILL says during setup FindMy will be using "this address and id" which is not mine. Nothing is turned on nor signed in!

I feel like there is something corrupted. How can it be signed out of everything and FindMy turned off, then when I sign in via iCloud on a fresh install it still doesn't use my ID for FindMy, but does for everything else?

Have a look at this, which is what the previous owner should have done when your Mac was sold or given to you.

What to do before you sell, give away, trade in, or recycle your Mac - Apple Support

Note especially, in that link, the complete signing out of iCloud, which would be what the previous owner should have done but from what you describe, did not apparently do. Because of that, the device is still connected to that Apple ID and without the password from the previous owner, I don't think you can "free" this Mac so you can use it as you wish. If I am correct (I am hoping someone will point out something simple that I overlooked but I doubt that will happen), this is a huge problem because the previous owner can lock and even remotely wipe the computer.

I think your best course of action is to contact the previous owner and ask them to help you log out of that previous Apple ID. There may be a way for the previous owner to disassociate the computer from their Apple ID, remotely, but I'm not sure. You can also contact Apple for help with this, but keep in mind that unless you can show them convincingly that this Mac belongs to you, they might not help you, as to them, it might look like the original owner is no longer in physical possession of the computer (you are). If you can show proof that the computer was sold/transferred to you, Apple MIGHT be able to help.

Let us guess.

This Apple computer was purchased Privately or possible from some Website that sells Apple Computers

The price was so good, it was almost unbelievably inexpensive compared to a New Apple Computer

Yes, the Activation Lock is not On

But, as others have mentioned rightly

The Previous Owner has not properly prepared the computer for re-sale

If purchased Privately - take it back to them and have them fix this issue as outlined by @steve626

If purchased from a Website - contact them and ask to Return the computer for a Full Refund

Suggestion in regarding to buying Used Apple Products

Purchased Used Apple Products, iPhone, iPad, iWatch, Computers should be purchased from Directly from Apple or an Apple Certified Service Centre

They are well acquainted in what needs to be done before they will allow a device to be sold

Although you are the only user …

… presumably you are not the “original” owner / user ???