i cannot sign in into my mac ios app store, it keeps telling me connection failed?

If this is a used device, you will need to contact the seller to have them log out of iCloud or go to iCloud.com/Find My Phone and erase the device. If you can’t do that, the device is useless.

If you are the original owner, take the device, the original purchase receipt, and a photo ID to the nearest Apple Store.

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