It also persists through iCloud backup/restores. The issue originally happened on an older iPhone but I have a new phone and the issue still exists.

I think I may have been mistaken when I said the advertised name was corrupted. It appears that the advertised name is updating correctly but the peripheral name isn't. It's different between the device where it works and where it doesn't. On either device I cannot get the (i) to show up in bluetooth settings. I tried resetting network settings too but the peripheral name is still showing up different between the two devices. Is there any other way to clear the cached peripheral name?

Thank you. On the other phones it’s working correctly with the correct name. I’ve tested a few devices and it seems to show the correct name on all except my main device. I’ve been using Bluetooth debugging apps that show the raw Bluetooth info. Is there a way to manually forget a Bluetooth low energy device from settings? When paired there is no “i“ icon next to it so I can’t change the name or forget it.