2020 MacBook, used: Old MacBook name shows up on AirDrop

Hi. I bought a MacBook Air secondhand a few days ago. I deleted the old user's admin account after I created a new admin account. I went into Sharing on System Preferences and changed the name of my computer as well. But whenever I use AirDrop or make a phone call and hit the "audio" button, the old name of the computer shows up as a discoverable option together with the new computer name. Just to see if it would work, I tried sharing a photo with the old computer name via AirDrop but it just stalled out at "Sending".

Why does the old computer name show up alongside the new one? How do I delete it completely?