How to remove your Best Buy account
Contact customer support via phone: 1-800-BESTBUY.
Or drop them a message on the forum: https://forums.bestbuy.com/
Should have been a lot easier, but at least they respond to your request.
Helpful Trick: Removing online data
Publicly visible text/images often aren’t properly removed even when you succeed in removing an account. Try editing or removing them manually before removing the account itself. If you’re unsure what happens to your tracks: this can be found mostly in the Terms of Service/Privacy Policy; otherwise you can always contact Best Buy and ask personally. By the way, removal requests don’t necessarily mean your data will actually be removed (e.g. due to legal obligations).
Helpful Trick: Remove third-party logins
If you signed up for Best Buy using a third-party login such as Facebook or Twitter, you probably want to revoke all access from Best Buy. Click here to find out how.