Maximum free accounts reached on second-hand iPad

1. You should use your existing Apple Account, if you already have one. It is rarely needed to have multiple Apple Accounts, and that may prevent convenient cross-device services, or even group services.
2. Alternatively to creating a new Apple Account on the device through Settings (during setup or later), you can create a new Apple Account on the web. No Apple device needed per se. No maximum applies. Such accounts would not include the complimentary 5 GB iCloud, and you won’t get an @icloud.com email address (supply your own email address instead). How to create a new Apple Account - Apple Support
3. The other support document suggests that the limit is per year. So optionally try again in 365 days since the last account creation on that device.

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