Thank you for the screenshot. You do have digital key for Windows 10/11 Home Single Language, 6F4BT is the last 5 of the generic key for this edition, which indicates digital license.
With digital license, it is extremely important that you do not remove the old device from your Microsoft account, because it relies on the troubleshooter to find the old device first, so that it can transfer it from the old to the new. This following instruction would have been what you should do:
go to Settings > System > Activation, run the troubleshooter, choose the hardware change option. When it asks you where it is installed on right now, you should choose the old device name. Then click on Activate button. And on the next screen when it asks you where to transfer it to, choose your new device name.
Since you have already removed the old device from your account, your only solution is via Microsoft support for manual activation. Use the exact step below to chat with support, and make sure you have proof of purchase.
Open the "Get Help" app on your computer (just search for it in the Start menu). or go to https://support.microsoft.com/contactus, Type "Billing" and press Enter. On the next screen, click "Contact support" at the bottom of the page, then choose "Windows" > "Manage my subscription". You’ll then see the option to chat with a Microsoft support agent.