If you own AirPods, it is likely your AirPods and they are temporarily having issues communicating with the Find My network.
From https://support.apple.com/en-us/HT212227:
If AirPods or a Find My network accessory is detected but the Find My app has issues connecting to them or to the server at that time, this alert is displayed: Unknown Accessory Detected. This alert will display only if a set of AirPods or a Find My network accessory is detected near you, not an AirTag. These could be borrowed AirPods, or AirPods inadvertently left behind by a friend or family member.
EDIT: Sorry, meant to reply to OP