Sold Macbook never went out from my Find Devices list

Hi, and welcome to the Apple (user-to-user) Community!

Re: Sold Macbook never went out from my Find Devices list

Wondering if you may have overlooked removing your Mac from the list before it was sold:

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

Seems it is not too late:

Check your Apple ID device list to find where you're signed in - Apple Support

says you can:

"Use the web to remove a device

1. Sign in to appleid.apple.com, then select Devices.
2. Select the device to find its details, then select Remove from Account.
3. Review the message that appears.
4. Click again to confirm you want to remove the device.

Also says how to:

"Permanently remove a device from your account page

If you're still signed in with your Apple ID on the device, it may reappear on your account page the next time your device connects to the internet. To permanently remove the device from your account page, sign out of iCloud, iTunes & App Stores, iMessage, FaceTime and Game Centre on that device, or erase that device."

Seems it may be too late for that, unless you know the new owner, and gain their co-operation.

All the best :-)