Each Apple ID may be attached up to 16 AirTags and can to keep track all 16 objects at once.
How to Fix AirTag Not Connecting Error "Maximum Items Added"
Many iPhone and iPad users are having problems adding or connecting to Airtags. The Airtag can not connect, and the error message "Maximum Objects Added - To add AirTag, open FindMy and delete one of the items that is associated to your Apple ID" appears. The problem is noticed with many iPhone models such as the iPhone 13/12 Pro, Apple Watch, and iPad Pro, among others. Even when no Airtag is added the iPhone displays an error indicating that it has hit the maximum limit.
If you are unable to connect Airtag and do not have 16 devices connected and receive the error "Maximum items added - To Add an AirTag, Open FindMy to delete one of the objects that is paired to your Apple ID," please try the methods below to see if they assist.1. You can try sign out of your iCloud account on your iPhone and then sign back in.
The problem is said to be related to an AirPods firmware upgrade, and the problem began to occur for numerous customers following the revisions. Because Apple will be releasing a permanent patch for the issue, we urge that you keep your Apple devices up to date.
3. Another alleged remedy is that when you add an AirTag, the Find My app incorrectly counts all the devices and objects you're monitoring to determine if you have too many, and the solution is to delete a device, add the AirTag, and then put the device back.
Things you can track with Apple's AirTag
Keys with AirTag Keychains
Luggage, Bags and Backpacks with AirTag bag charm
Cash and Cards with AirTag Billfold or Card Holder
Passport with AirTag Travel Wallet